Washington — President Obama and Secretary of State Hillary Rodham Clinton condemned a rocket attack on the U.S. mission in Benghazi, Libya, that took the lives of four Americans, including U.S. Ambassador John Christopher Stevens.

Stevens, a 21-year U.S. diplomat, and three U.S. Embassy personnel were killed when they went to the eastern city of Benghazi to try to evacuate mission staff late September 11 during a riot in which a mob fired machine guns and rocket-propelled grenades at the mission. Also on September 11, demonstrators attacked the U.S. Embassy in Cairo, breaching the embassy walls and destroying the U.S. flag.

“I strongly condemn the outrageous attack on our diplomatic facility in Benghazi,” Obama said in a prepared statement September 12. The president added that the diplomats “exemplified America’s commitment to freedom, justice and partnership with nations and people around the globe, and stand in stark contrast to those who callously took their lives.”

Obama ordered the U.S. government to provide all necessary resources to support the security of U.S. personnel in Libya and to increase security at diplomatic posts around the globe. He said at the White House September 12 that those responsible for the attack on the mission will be brought to justice.

“While the United States rejects efforts to denigrate the religious beliefs of others, we must all unequivocally oppose the kind of senseless violence that took the lives of these public servants,” Obama said.

At the State Department September 12, Clinton told journalists that “this is an attack that should shock the conscience of people of all faiths around the world. We condemn in the strongest terms this senseless act of violence and we send our prayers to the families, friends and colleagues of those we’ve lost.”

But Clinton also said that this attack on the U.S. mission was by “a small and savage group” and not the Libyan people or the Libyan government. “Libyans stood and fought to defend our post. Some were wounded. Libyans carried Chris’ body to the hospital and they helped rescue and lead other Americans to safety.”

It was an especially difficult time for the United States because this attack and the similar attack in Cairo occurred on the 11th anniversary of the terrorist attacks on the United States in 2001, Clinton noted.

Clinton telephoned Libyan President Mohamed Yousef el-Magariaf September 11 to coordinate additional support to protect Americans in Libya.

“President Magariaf expressed his condemnation and condolences and pledged his government’s full cooperation,” Clinton said in a State Department statement.

“Some have sought to justify this vicious behavior as a response to inflammatory material posted on the Internet,” Clinton added. “The United States deplores any intentional effort to denigrate the religious beliefs of others. Our commitment to religious tolerance goes back to the very beginning of our nation.”

“But let me be clear: There is never any justification for violent acts of this kind,” she said.

Ambassador Susan Rice, the U.S. permanent representative to the United Nations, said September 12 in New York that "the United States has lost four brave individuals who, in President Obama’s words, exemplified America’s commitment to freedom, justice and international partnership.”

She noted that in Ambassador Stevens, the Libyan people lost a close friend — one who stood by them in their revolution and its aftermath, one who understood and shared in their aspirations, their culture and their traditions.

“He was passionate about his work to bring about a better future in Libya, and he cared deeply for the Libyan people,” Rice said. “He and the rest of his team risked their lives daily to support the Libyan people's democratic aspirations, including during the height of the revolution, when he represented the United States in Benghazi.”

On Capitol Hill, U.S. Senator Mitch McConnell of Kentucky said on the floor of the Senate that he and the members of the Senate join in condemning “the murder of these innocent Americans. And I support employing every available tool at our disposal to ensure the safety of Americans overseas and to hunt down those responsible for these attacks.”

Stevens, 52, is the first U.S. ambassador to be killed in the line of duty since 1979, when Adolph Dubs was killed in Afghanistan, according to the State Department’s Office of the Historian. Five U.S. ambassadors have been killed in the line of duty by terrorist acts, while two others died in plane crashes.

Stevens had served two previous diplomatic tours in Libya and directed the mission in Benghazi during the revolt against former Libyan leader Muammar Qadhafi.

Killed with Stevens was Sean Smith, a U.S. Foreign Service information management officer stationed at the Tripoli Embassy. The names of the other two personnel are being withheld until their families can be informed.

Defense Department spokesman Lieutenant Colonel Steven Warren told journalists that the Pentagon was working with the State Department on the president’s order for increased security around the world. He said the Pentagon would provide any support the State Department requests.

A special U.S. Marine fleet antiterrorism security unit was being dispatched to Tripoli and the U.S. Embassy to provide additional security, according to the Pentagon. In addition, U.S. Marines stationed at the embassy were being sent to the Benghazi mission to provide additional security.