The White House said it is not yet clear who is responsible for a suicide bombing on Friday at the U.S. embassy in Turkey, the second attack on a U.S. mission in four months, Reuters reported.
"The attack itself was clearly an act of terror," said Jay Carney, White House spokesman, in a briefing with reporters.
A massive explosion took place on the entrance of the U.S. Embassy building in Ankara, TRT Haber TV channel said on Friday.
According to Hurriyet newspaper, three people were killed as a result of the explosion. According to a preliminary version, a suicide bomber carried out the explosion.
A large number of people were injured, according to the report.
Turkish police did not rule out the possibility that the explosion was carried out by a suicide bomber from the Al Qaeda terrorist organization, as the son-in-law of the organization's former leader Osama bin Laden was recently detained in Istanbul.