[Updated at 11:59 a.m. ET] Istanbul police identify the bomber as Ecevit Shanli, a member of DHKP-C, a Marxist-Leninist terror group.
[Updated at 9:19 a.m. ET] U.S. State Department spokesperson Victoria Nuland issues a statement on the attack: "We can confirm a terrorist blast at a checkpoint on the perimeter of our embassy compound in Ankara, Turkey, at 1:13 p.m. local time. We are working closely with the Turkish national police to make a full assessment of the damage and the casualties, and to begin an investigation. We will share more information as it becomes available."
[Updated at 8:10 a.m. ET] The person killed in the bombing outside the U.S. embassy is a Turkish embassy guard, a senior U.S. official tells CNN. Two other people were wounded and neither is American, the official said.
[Updated at 7:38 a.m. ET] The blast happened shortly after 1 p.m. local time. The U.S. Embassy would normally be open for business at that hour, CNN's Ivan Watson reports.
[Updated at 7:31 a.m. ET] Video from the scene shows ambulances in the streets near the embassy. Security forces have closed off the area. U.S. officials have been unable to confirm details of the attack.
[Updated at 7:20 a.m. ET] Images from CNN sister network CNN Turk show a hole in a wall of a building across the street from the U.S. Embassy in Ankara, Turkey.
[Updated at 7:05 a.m. ET] One person was killed and two others were wounded by a suicide bomber who blew himself up outside the U.S. Embassy in Ankara, according to Ankara police.
[Posted at 6:45 a.m. ET] CNN is working to confirm reports of an explosion near the U.S. Embassy in Ankara, Turkey. Turkey's semi-official news agency Anadolu is reporting the blast. Ambulances arrived to pick up injured people, the report said.