World

Photo: The Canadian Press. All rights reserved.

FILE - In this Monday, April 11, 2011 file photo, U.S. Ambassador/envoy Chris Stevens, center, accompanied by British envoy Christopher Prentice, left, speaks to Council member for Misrata Dr. Suleiman Fortia, right, at the Tibesty Hotel where an African Union delegation was meeting with opposition leaders in Benghazi, Libya. . (AP Photo/Ben Curtis, File)

The U.S. ambassador to Libya and three other Americans were killed in an attack on the U.S. Consulate in Benghazi by protesters angry over a film that ridiculed Islam's Prophet Muhammad.

Ambassador Chris Stevens, 52, died as he and a group of embassy employees went to the consulate to try to evacuate staff as the building came under attack by a mob firing machine-guns and rocket-propelled grenades. He was the first U.S. ambassador to be killed in the line of duty since 1979.

President Barack Obama ordered increased security to protect American diplomatic personnel around the world.

"I strongly condemn the outrageous attack on our diplomatic facility in Benghazi," Obama said, adding the four Americans "exemplified America's commitment to freedom, justice, and partnership with nations and people around the globe."

Libya's interim president, Mohammed el-Megarif, apologized to the United States for the attack, which he described as "cowardly." Speaking to reporters, he offered his condolences on the death of the four Americans and vowed to bring the culprits to justice and maintain his country's close relations with the United States.

The three Americans killed with Stevens were security guards, he said.

"We extend our apology to America, the American people and the whole world," el-Megarif said.

The attack in Libya came hours after Egyptian protesters climbed the walls of the U.S. Embassy in Cairo, pulling down the American flag and temporarily replacing it with a black Islamic banner.