Amr Abdallah Dalsh / Reuters

Iran's President Mahmoud Ahmadinejad meets people as he visits the Al-Hussein mosque, named after Prophet Mohammed's grandson Hussein ibn Ali, in old Cairo on Feb. 5, 2013. Ahmadinejad was both kissed and scolded on Tuesday when he began the first visit to Egypt by an Iranian president since Tehran's 1979 Islamic revolution.

CAIRO -- Egypt's security arrested four men who were protesting outside a Cairo mosque, where the Iranian President Mahmoud Ahmadinejad was praying.

The men, including a Syrian, belong to the ultra-conservative Sunni Salafist movement.

One man threw a shoe at Ahmadinejad, a Shiite, who was never in any danger.

The Al-Hussein Mosque is revered by Shiite Muslims, who are widely disliked by conservative Sunni Muslims, including members of the Muslim Brotherhood. Egypt's President Mohammed Morsi was previously a member of the Brotherhood.

Many Sunni Muslim groups have denounced the Iranian president’s visit to Cairo and have called on Egypt’s government to prevent Ahmadinejad from visiting any religious sites that are significant to Shiite Muslims.

Ahmadinejad met with Sunni Islam's most senior scholar at Al Azhar shortly before he went to pray at the Al-Hussein Mosque.

Hussein Malla / AP

A Sunni gunman fires during clashes, in the northern port city of Tripoli, Lebanon, on May 14. Street battles pitting Lebanese Sunnis who generally support the Syrian uprising, against Alawite supporters of Assad's regime killed at least one person Monday, raising the death toll to four since Sunday. The clashes began Sunday after authorities detained an anti-Syrian Lebanese national.

Hussein Malla / AP

A Lebanese Sunni family run between white tarps hung to provide cover from snipers as they flee their house during clashes, in the northern port city of Tripoli, Lebanon, on May 14.

Reuters reports -- Two men were killed and at least 20 people were wounded in clashes between Alawite supporters of Syrian President Bashar al-Assad and Sunni Muslims in the Lebanese city of Tripoli, medical sources said on Monday.

Fierce clashes overnight shook the northern port city and sporadic fighting continued on Monday. Machineguns and rocket propelled grenades were used.

Tension between the Alawite and Sunni communities in Tripoli has been fuelled by the unrest in neighboring Syria, where Assad is seeking to crush a 14-month-old uprising which began with largely peaceful protests against his rule but has become increasingly militarized.

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Stringer / Reuters

A Sunni Muslim gunman carries a machinegun during clashes at the Sunni Muslim Bab al-Tebbaneh neighbourhood in Tripoli, northern Lebanon, on May 14. Two men were killed and at least 20 were wounded in clashes between Alawite supporters of Syrian President Bashar al-Assad and Sunni Muslim fighters in the Lebanese city of Tripoli, medical sources said on Monday. Fierce clashes overnight shook the northern port city and sporadic fighting continued on Monday morning, with fighters firing machineguns and rocket propelled grenades.

Reuters

A Sunni Muslim gunman fires his rifle as others help an injured colleague during clashes at the Sunni Muslim Bab al-Tebbaneh neighborhood in Tripoli, northern Lebanon, on May 14. Two men were killed and at least 20 people were wounded in clashes between Alawite supporters of Syrian President Bashar al-Assad and Sunni Muslims in the Lebanese city of Tripoli, medical sources said on Monday. Fierce clashes overnight shook the northern port city and sporadic fighting continued on Monday. Machineguns and rocket propelled grenades were used.

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In the desert island nation of Bahrain, Shia protesters are calling for the minority Sunni monarchy to give up its control over top government posts and to address deep grievances by Shiites, who claim they face systematic discrimination and poverty and are effectively blocked from key roles in public service and the military. To better understand this tiny nation that has been newly thrust into the headlines this week, we're sharing several images by Jonathan Lewis who traveled to Bahrain last fall during quieter times to cover the economy and elections. 

Jonathan Lewis

Bahrain's financial district, harbor and shoreline developments such as the Bahrain World Trade Centre are built on reclaimed land as the country attempts to diversify its economy. The island nation is one of the smallest in the world, just 3.5 times the size of Washington, D.C. 

Jonathan Lewis

Migrant workers make up a significant share of the manual labor force in the state of Bahrain, with many workers coming from India, Nepal, Pakistan and southeast Asia. Many workers complain that they are charged high fees for entering the country, which they then have to pay back to their agents or employers. Many also complain that their passports are taken from them on arrival in Bahrain.

Jonathan Lewis

The ruling Sunni Al Khalif Royal family are accused of stealing land and selling it for their own fortune in a country where tensions are high due to the regular detention of members of the Shia majority who make up 70% of the population of Bahrain.

Jonathan Lewis

Designed to look like the sails of the traditional Dhows that head out to sea every evening to go pearl fishing, the Bahrain Financial Harbor, with the World Trade Centre in the distance, is one of the prize developments in Bahrain. With limited oil compared to its petroleum-rich neighbors like Saudi Arabia, Bahrain is relying on banking to shore up its economy.

Jonathan Lewis

Tensions were high during the October 2010 general election following the  detention of 250 Shia who were accused of terrorism by the government. International campaign groups such as Human Rights Watch stated that some detainees were tortured. The outcome of the election, which favored the minority Sunnis, was disputed by the majority Shia group who feel under-represented in Bahrain due to gerrymandering of electoral districts.

Explainer: Tiny nation, big history: What you need to know about Bahrain

Slideshow: Bahrain protest crackdown