Robert F. Bukaty / AP

A moment of silence in honor of the victims of the Boston Marathon bombing is observed on Boylston Street near the race finish line, exactly one week after the tragedy, on April 22, in Boston, Mass.

Robert F. Bukaty / AP

A woman wipes a tear at a memorial for the victims of the Boston Marathon bombing on Boylston Street near the race finish line, on April 22, in Boston, Mass. At 2:50 p.m., exactly one week after the bombings, many bowed their heads and cried at the makeshift memorial on Boylston Street, three blocks from the site of the explosions, where bouquets of flowers, handwritten messages, and used running shoes were piled on the sidewalk.

Kevork Djansezian / Getty Images

People in office buildings watch a moment of silence near the finish line of the Boston Marathon bombings on the one week anniversary of the bombings on April 22, in Medford, Mass.

By Matthew DeLuca, Staff Writer, NBC News

Boston observed a moment of silence at 2:50 p.m. Monday – exactly one week after an annual springtime rite in the city was shattered by a pair of explosions that killed three people and injured more than 200, including some who lost legs.

From the race’s finish line on Boylston Street to the floor of the New York Stock Exchange, mourners inside and out of Boston took a moment to remember those they lost. Continue reading.

Jessica Rinaldi / Reuters

Officials line Boylston Street near the site of the explosions as they observe a moment of silence for the victims of the Boston Marathon bombings in Boston, Mass., on April 22.

Brendan McDermid / Reuters

Traders on the floor at the New York Stock Exchange join the moment of silence in honor of the Boston Marathon victims, on April 22.

Robert F. Bukaty / AP

Lt. Mike Murphy of the Newton, Mass., fire dept., carries an American flag down the middle of Boylston Street after observing a moment of silence in honor of the victims of the Boston Marathon bombings, on April 22, in Boston, Mass.

Slideshow: Boston bombings

Dominick Reuter / Reuters

Cheers filled the streets after a Boston Marathon bombing suspect was captured alive but wounded Friday night — following a daylong manhunt that shut down the city.

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Previously on PhotoBlog:

• Infrared police chopper images show Boston Marathon suspect hiding in boat
• Patriotism runs high at the Boston Bruins hockey game
• Marathon's deadly moments captured from office building above finish line

Updated with video:

Massachusetts State Police

Massachusetts State Police

Above: Infrared images released by the Massachusetts State Police Air Wing appear to show Boston Marathon bombing suspect Dzhokhar Tsarnaev on Friday, April 19, hiding in a Watertown, Mass., resident's boat in the resident's backyard. Below: A police vehicle uses a boom to inspect the boat.

Related story: Secret weapon? How thermal imaging helped catch bomb suspect

Massachusetts State Police

Massachusetts State Police

Slideshow: Search for suspects in Boston Marathon bombings

Jared Wickerham / Getty Images

Cheers filled the streets after a Boston Marathon bombing suspect was captured alive but wounded Friday night — following a daylong manhunt that shut down the city.

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Barcroft Media /Landov

These images show Tamerlan Tsarnaev, identified by investigators as Suspect 1 in the Boston Marathon bombings. The older of the two brothers sought by law enforcement, the 26-year-old was killed in a firefight with police. He was born in Russia, and became a permanent legal resident of the United States in 2007, law enforcement officials said.

Tamerlan Tsarnaev's brother, Dzhokhar, 19, remained at large on Friday.

The suspect in the black hat in photos released by the FBI, Tsarnaev studied at Bunker Hill Community College in Boston and aspired to become an engineer, according to a profile in a Boston University graduate magazine in 2010. He wanted to box for the U.S. Olympic team, according to the profile.

According to an article in The Lowell Sun newspaper, Tsarnaev boxed in a 2004 tournament as part of a program called Golden Gloves. “I like the USA,” he told the newspaper at the time.

In the Boston University magazine photospread, Tsarnaev is shown working out at the Wai Kru Mixed Martial Arts Center in Boston, Mass. He is quoted as saying he loves the movie Borat, and describes himself as a Muslim who does not smoke or drink. “I don’t have a single American friend,” he said. “I don’t understand them.”

Barcroft Media /Landov

Barcroft Media /Landov

Barcroft Media /Landov

Barcroft Media /Landov

Barcroft Media /Landov

Barcroft Media /Landov

Barcroft Media /Landov

Barcroft Media /Landov

Barcroft Media /Landov

Barcroft Media /Landov

Barcroft Media /Landov

Editor's note: Faces were blurred by the photographer's agency to obscure the identity of other individuals in the pictures.

Related:

• Massive Boston manhunt drags on; anxiety grips city
• Bombing suspect on the run became US citizen last year on Sept. 11
• Timeline of terror hunt: From release of suspect photos to rolling shootout

Glenn Depriest / Getty Images

Tamerlan Tsamaev, left, fights Lamar Fenner during the 201-pound division boxing match during the 2009 Golden Gloves National Tournament of Champions May 4, 2009 in Salt Lake City, Utah.

Jessica Rinaldi / Reuters

Boston Bruins Dennis Seidenberg observes a moment of silence for the victims of the Boston Marathon bombings before the start of an NHL hockey game against the Buffalo Sabres at TD Garden in Boston, Mass., on April 17, 2013. This is the first sporting event to be held in Boston after the explosions that killed three and injured more than one hundred at the Boston Marathon.

Jim Rogash / Getty Images

A Bruin fans shows her support for the efforts of the Boston police and firefighters before a game Wednesday night.

Just two days after the tragic bombing of the Boston Marathon, hockey fans gathered at the city’s TD Garden to cheer for their team.

Attendees accepted and dealt with heightened security as they entered the building and made way to their seats, and the crowd cheered as the color guard brought the flag onto the ice.

Then, thousands of voices joined together for one of the most powerful renditions of the national anthem you’ll ever hear. Play this NBC Sports video to see it happen.

Elise Amendola / AP

A fan wearing a United States flag raises his arms to be checked on the way into TD Garden prior to the game.

An amateur photographer who works in a downtown Boston office captured grim photos of the moment when the bombs went off as the marathon was finishing on Monday.

"I went to the window and I was looking in the direction of the finish line. I saw simultaneously a runner go down, a huge explosion, and then a deafening roar," Benjamin Thorndike said. "I had my camera in my hand, and I just pushed the rapid-shutter button down and just took 25 pictures over the course of what felt like a long time, but I think it was only 15 or 20 seconds."

None of the people in Thorndike's photos have been identified.

Courtesy Ben Thorndike

Courtesy Ben Thorndike

Courtesy Ben Thorndike

Courtesy Ben Thorndike

Courtesy Ben Thorndike

Courtesy Ben Thorndike

Courtesy Ben Thorndike

Courtesy Ben Thorndike

Hear Thorndike describe the experience in his own words, and watch the pictures in a video sequence, here.

Related content:

• As Boston bombing photos and videos pour in, where do investigators begin?
• Slideshow: Aftermath and reaction following Boston bombings
• Anatomy of a bombing: Photos show battery, wires used in device

Elise Amendola / AP

Two men in hazardous materials suits put numbers on the shattered glass and debris as they investigate the scene at the first bombing on Boylston Street in Boston on April 16, 2013 near the finish line of the 2013 Boston Marathon.

From a blood-covered zipper pull to a dented blue-and-silver battery, the Boston Marathon bombing site has yielded important forensic evidence that authorities will use to profile and track suspects.

New photos of the crime scene where white-suited FBI specialists are gathering evidence are testament to the power of the two bombs, which twisted a metal pressure cooker apart and sprayed debris on rooftops.

The force of Monday’s blast killed three people and tore off the limbs of other victims, but dozens of clues were left behind.

Joint Terrorism Task Force of Boston via Reuters

Boston Marathon bomb scene pictures taken by investigators show the remains of an explosive device. The photos were produced by the Joint Terrorism Task Force of Boston, provided to Reuters April 16, 2013 by a U.S. government official who declined to be identified.

There are orange and black wires marked with manufacturer details, half-inch nails known as brads, a made-in-China battery emblazoned “3000,” a green circuit board less than 2-inches long, and a shredded nylon bag.

Joint Terrorism Task Force of Boston via Reuters

Separately, they look like pieces of junk you might find in a work shed. Together, they are road map to terror and tragedy.

Investigators, led by the FBI through the Joint Terrorism Task Force, are already analyzing each fragment. No detail – not even the insignia on the zipper pull that could be from the bomber’s bag – will escape attention.

Authorities will try to figure out where the components were bought and compare them to devices used in other attacks. Ultimately, they hope the clues will lead them to the person or group that built, planted and detonated the bombs at the finish line of the iconic race.

One thing is already clear.

“They functioned as designed,” one official told NBC News.

“It appeared to be built from scratch but with a sophisticated triggering mechanism. And frankly, at the end of the day, all bombs are crude devices, and it is the way they are triggered that can be sophisticated.”  

Joint Terrorism Task Force of Boston via Reuters

Joint Terrorism Task Force of Boston via Reuters

Joint Terrorism Task Force of Boston via Reuters

Joint Terrorism Task Force of Boston via Reuters

Joint Terrorism Task Force of Boston via Reuters

Joint Terrorism Task Force of Boston via Reuters

Joint Terrorism Task Force of Boston via Reuters

Related:

• Life disrupted: Eerie scenes after Boston Marathon bombings
• Marathon's deadly moments captured from office building above finish line
• Video -- Former ATF agent: ‘These are hellish’ devices

Spencer Platt / Getty Images

The unfinished meals of fleeing customers are left on tables at an outdoor restaurant near the scene of a twin bombing at the Boston Marathon on April 16, 2013 in Boston, Mass. The twin bombings, which occurred near the marathon finish line, resulted in the deaths of three people while hospitalizing at least 128. The bombings at the 116-year-old Boston race, resulted in heightened security across the nation with cancellations of many professional sporting events as authorities search for a motive to the violence.

Justin Lane / EPA

Bags of people's belongings gathered not far from the finish line of the Boston Marathon as an investigation continues into dual bombings at the site, in Boston April 16.

While there have been many moving photos of the bombings at the Boston Marathon, these quiet, empty moments are powerful in their own way. The plates full of uneaten food at an abandoned restaurant suggest the chaos immediately following the explosions, causing people to flee leaving unfinished drinks and unpaid bills. Yellow bags full of runners’ personal belongings, intended to be picked up after crossing the finish line, instead evoke unrealized dreams of completing a marathon. The silver thermal blankets that so often are worn proudly following a race, yesterday served a much different purpose and blanketed injured runners.

Related:

• Marathon's deadly moments captured from office building above finish line
• Martin Richard, 8, killed in Boston Marathon blast
• The man in the hat at Boston Marathon finish line: Carlos Arredondo didn't set out to be hero

Spencer Platt / Getty Images

Unused thermal blankets for marathon participants are piled near the scene of a twin bombing at the Boston Marathon on April 16, in Boston.

Jessica Rinaldi / Reuters

Blood in seen on the sidewalk in front of a candy store advertising a Marathon Monday sale a day after two explosions at the Boston Marathon in Boston, on April 16.

Brian Snyder / Reuters

Two police officers walk down Boylston Street, away from the finish line of the Boston Marathon in Boston on April 16.

Slideshow: Aftermath and reaction following Boston bombings

Shannon Stapleton / Reuters

Heightened security, empty streets, and memorials mark the the day after the Boston Marathon bombings.

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Brian Snyder / Reuters

A woman plays with her dogs as snow accumulates along Commonwealth Avenue in Boston, Massachusetts February 8, 2013 during what is forecasted to be a major winter snow storm.  Read the full story.

Slideshow: Northeast storm

Matt Campbell / EPA

A dangerous winter storm churned Friday into the Northeast as forecasters warned of a whiteout.

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Steven Senne / AP

People walk through a portion of the Boston Common covered with American flags, in Boston, May 23.

Steven Senne / AP

Buttons featuring the likeness of fallen U.S. Marine Lance Cpl. Alexander S. Arredondo and his brother Brian Luis Arredondo, who took his own life following the death of Alexander, are attached to an American flag in front of thousands of flags planted in the Boston Common, in Boston, May 23. Relatives and volunteers planted the 33,000 flags in the historic park in advance of the Memorial Day weekend, in tribute to Massachusetts soldiers killed in conflicts as far back as the Civil War. Alexander was killed in 2004 in Iraq.

Over 200 volunteers spent Wednesday planting flags for Memorial Day on the grounds of Boston Common in downtown Boston in honor of those who served and died for our country.  The 33,000 flags represent all of the fallen soldiers from Massachusetts who have died since the civil war.

Today, Massachusetts Gov. Deval Patrick will honor veterans at an event at Soldiers and Sailors Monument, where all the names of the state’s soldiers who have been killed in Iraq and Afghanistan will be read.  The city will also hold services and parades over the holiday weekend.

• More about Lance Cpl. Alexander S. Arredondo from the Military Times
• Story: Man who torched self after news of his son’s death will recover
• Story: Father of slain Marine pleads for an end to war
• NYT Story: A Father with a coffin, telling of war’s grim toll
• Fallen Marine’s brother takes his own life

More photos from Memorial Day on PhotoBlog