The attacker was a Marxist:
http://www.usatoday.com/story/news/world/2013/02/01/turkey-embassy-bomb/1882475/
Turkish Interior Minister Muammer Güler told reporters that the attacker was Ecevit Sanli, a member of an outlawed leftist group that news media reported as being the Revolutionary People’s Liberation Party/Front (DHKP/C). The suspect in the attack spent eight months in prison for attending illegal demonstrations, Turkish news media said.