The U.S. ambassador to Libya was killed on Wednesday in the U.S. Consulate in Benghazi after being attacked by armed forces.

Ambassador Christopher Stevens and three other Americans died after gunmen attacked the consulate apparently in protest of a U.S. film they considered blasphemous to the prophet Muhammad.

U.S. President Barack Obama held an emergency countermeasures meeting upon hearing news of the attack on the consulate and vowed to “work with the Libyan government to bring to justice the killers” behind the latest attack.

Obama added that he also directed his administration to increase security at U.S. diplomatic posts around the world.

U.S. Secretary of State Hillary Clinton said “the United States deplores any intentional effort to denigrate the religious beliefs of others,” adding that “there is never any justification for violent acts of this kind."

Clinton made the comment as she said that "some have sought to justify this vicious behavior as a response to inflammatory material posted on the Internet.”