At least eleven people were killed in a large explosion in the Turkish capital on Wednesday, believed to have been caused by a car bomb, local media reported.
The explosion occurred during rush hour in an area close to where military headquarters and parliament are located.
Governor Mehmet Kiliclar said the bomb appeared to have targeted a convoy of buses carrying military personnel, adding that five people died and 10 were wounded.
News reports said some cars caught fire and dozens of ambulances were sent to the scene.
Dark smoke could be seen billowing from a distance.
The explosion was an act of terrorism, said Deputy Prime Minister Bekir Bozdag on Twitter.
Prime Minister Ahmet Davutoglu, who had been due to leave for a trip to Brussels later on Wednesday, cancelled the trip, an official in his office said.