Jonathan Sunderman / US Navy via Reuters

Guided-missile destroyer USS Porter (DDG 78) is seen after a collision with the bulk oil tanker M/V Otowasan in the Strait of Hormuz, Aug. 12. No one was hurt and shipping traffic in the waterway, through which 40 percent of the world's seaborne oil exports pass, was not affected, officials said.

The collision nevertheless left a gaping hole in the starboard side of USS Porter, a guided-missile destroyer, but no one was injured on either vessel, the U.S. Navy said in a statement. The collision with the Panamanian-flagged bulk oil tanker M/V Otowasan occurred at approximately 1 a.m. local time. 

The cause of the incident is under investigation, the Navy said, adding that there were no reports of spills or leakages from either the USS Porter or the Otowasan. 

Reported by NBC News wire services

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Jonathan Sunderman / US Navy via Reuters

Reuters TV / Reuters

An Iranian warship launches a missile in this still image taken from footage released by Islamic Republic of Iran Broadcasting (IRIB) on Jan. 1.

The exercise covers a 1,250-mile stretch of water beyond the Strait of Hormuz, including parts of the Indian Ocean and the Gulf of Aden.

The drill could bring Iranian ships into proximity with U.S. Navy vessels that operate in the same area.

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Reuters TV / Reuters

Iranian warships take part in a naval drill in this still image taken from footage released by Islamic Republic of Iran News Network on Jan. 1.

Hamed Jafarnejad / Fars News via Reuters

An Iranian soldier participates in the Velayat-90 war game on Sea of Oman near the Strait of Hormuz in southern Iran on Dec. 28, 2011.

Foreign media are subject to severe restriction on their ability to make and distribute news pictures in Iran. So, when images like this move right after Iran threatens to close the Strait of Hormuz you know that the Tehran is sending a clear message. In fact, Iran’s navy chief Habibollah Sayyari told the country’s English language press on Wednesday that closing the Strait of Hormuz will be easier than drinking a glass of water.

At the same time the U.S. Navy’s 5^th fleet warned Iran that any disruption of traffic flowing through the Strait of Hormuz oil route “will not be tolerated.”

About 20% of the world's oil supply transits throught the Strait of Hormuz.

Msnbc.com news services report: Western nations are growing increasingly impatient with Iran over its nuclear program. The U.S. and its allies have accused Iran of using its civilian nuclear program as a cover to develop nuclear weapons. Iran has denied the charges, saying its program is geared toward generating electricity and producing medical radioisotopes to treat cancer patients.

The U.S. Congress has passed a bill banning dealings with the Iran Central Bank, and President Barack Obama has said he will sign it despite his misgivings. Critics warn it could impose hardships on U.S. allies and drive up oil prices.

Iran is the world's fourth-largest oil producer, with an output of about 4 million barrels of oil a day. It relies on oil exports for about 80 percent of its public revenues. Read more...

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