Updated

Recent large-scale killings in the Middle East:

HOULA, SYRIA, MAY 12, 2012: Activists say men in civilian clothes gunned down people in the streets and stabbed women and children in their homes after large anti-government protests in Houla, a group of villages in central Syria. The U.N. says at least 108 people were killed, including 34 women and 49 children. The attack came 15 months into an uprising against President Bashar Assad that has killed thousands of people. Assad's regime denies its forces carried out the attack.

HALABJA, IRAQ, 1988: In the deadliest chemical weapons attack against civilians, Saddam Hussein's regime unleashed poison gas in the Kurdish town of Halabja in northern Iraq, killing up to 5,000 people. Saddam suspected the non-Arab Kurds of siding with Iran as a war between the two was winding down and a rebellion in the north was taking root. Photos showed the bodies of men, women and children lying in the streets. Both Saddam and Ali Hassan al-Majid — widely known as "Chemical Ali" — were later executed for the attack and other crimes against humanity.

SABRA AND SHATILA REFUGEE CAMPS, LEBANON, 1982: Israeli-backed Christian Phalange militiamen entered two Palestinian refugee camps in the Lebanese capital of Beirut, killing between 1,200 and 1,400 men, women and children. The Christian militiamen were sworn enemies of the late Yasser Arafat's PLO. An Israeli commission of inquiry later found Ariel Sharon, defense minister at the time, indirectly responsible.

HAMA, SYRIA, 1982: Then-Syrian President Hafez Assad, the father of the current leader, cracked down on a Muslim Brotherhood-led rebellion in the northern city of Hama. The Syrian forces, led by the president's brother and special forces from their minority Alawite sect, razed much of the city in a three-week air and ground attack, killing between 10,000 to 20,000 people. It has been described as the single deadliest attack by any Arab government against its own people.