A suicide bomber who attacked the U.S. Embassy in the Turkish capital spent four years in prison on terrorism charges prior to his release for a brain disorder contracted while on hunger strike, a Turkish official said Saturday.
The 40-year-old bomber, Ecevit Sanli, reportedly detonated an explosive device on the outside perimeter of the American Embassy in Ankara Friday, killing himself and an embassy guard in a terrorist attack whose motives are under investigation.
The official, who spoke on condition of anonymity, said that Sanli was arrested in 1997 for membership in the outlawed Revolutionary People's Liberation Party-Front, or DHKP-C, which has claimed responsibility for assassinations and bombings since the 1970s.
The group has been designated a terrorist organization by the United States but had been relatively quiet in recent years.
The attack was initially believed to be the work of either Al Qaeda or a proxy for Iran. Turkish officials, though, said the bombing was linked to leftist domestic militants.
The White House and U.S. State Department said Friday it was too early to determine who is behind the bombing. The attack, nearly five months after the assault on the U.S. consulate in Benghazi, Libya, comes as John Kerry was formally sworn in as secretary of State Friday.
"We strongly condemn what was a suicide attack against our embassy in Ankara," White House Press Secretary Jay Carney said at Friday's briefing in Washington.
Carney called the strike an "act of terror," but said officials "do not know at this point who is responsible or the motivations behind the attack."
According to U.S. military sources, the other individual killed in the Ankara attack was a Turkish national. All U.S. staff are safe at this time, though the U.S. consulate in Turkey has advised Americans in the country against visiting U.S. missions for the time being.
Another woman who was wounded reportedly was a well-known Turkish journalist.
State Department spokeswoman Victoria Nuland said U.S. officials were "working closely with the Turkish national police to make a full assessment of the damage and the casualties, and to begin an investigation."
The bomb appeared to have exploded inside the security checkpoint at the side entrance of the embassy, but did not do damage inside the embassy itself. Footage showed that the door had been blown off its hinges and debris littered the ground and across the road. An Associated Press journalist saw a body in the street in front of an embassy side entrance.
Police swarmed the area and several ambulances were dispatched. An AP journalist saw one woman who appeared to be seriously injured being carried into an ambulance.
The state-run Anadolu Agency on Friday identified the bomber as Sanli. Still, Nuland said who was responsible for the attack was an open question, amid recent warnings that terror groups are looking to hit western targets. In Turkey, U.S. Patriot missiles were recently deployed to the border with Syria, along with some U.S. troops, to operate the missile-defense system inside Turkey.
The U.S. Embassy put out a brief statement saying: "The US Embassy would like to thank the Turkish Government, the media, and members of the public for their expressions of solidarity and outrage over the incident."
On Capitol Hill, the new chairman of the House Foreign Affairs Committee said the attack "underscores the need for a comprehensive review of security at our diplomatic posts."
"This suicide bombing at our Embassy in Turkey is yet another stark reminder of the constant terrorist threat against U.S. facilities, personnel, and interests abroad," Rep. Ed Royce, R-Calif., said.
Fox News has learned that three House members also visited that embassy earlier in the week.
The embassy building is heavily protected. It is near an area where several other embassies are located, including that of Germany and France. Police sealed off the area and journalists were being kept away.
There was no claim of responsibility, but Kurdish rebels and Islamic militants are active in Turkey. Kurdish rebels, who are fighting for autonomy in the Kurdish-dominated southeast, have dramatically stepped up attacks in Turkey over the last year.
Yet homegrown Islamic militants tied to Al Qaeda have carried out suicide bombings in Istanbul, killing 58, in 2003. The targets were the British consulate, a British bank and two synagogues.
In 2008, an attack blamed on Al Qaeda-affiliated militants outside the U.S. Consulate in Istanbul left three assailants and three policemen dead.
In the November 2003 attack on the British consulate , a suspected Islamic militant rammed an explosive-laden pickup truck into the main gate, killing British Consul-General, Roger Short, and his assistant, Lisa Hallworth.
Turkey has become a harsh critic of the regime in Syria, where a vicious civil war has left at least 60,000 people dead. The first of six Patriot missile batteries being deployed to Turkey to protect against attack from Syria was declared operational and placed under NATO command on Saturday and others were expected to be operational in the coming days.
Fox News' Jennifer Griffin and The Associated Press contributed to this report.