US officials said tightened security at the American embassy in Ankara had helped save lives Friday when a bomber wearing a suicide vest attacked a checkpoint killing a Turkish guard.
A Turkish woman journalist has been seriously hurt and two local security guards were shaken up in the attack.
"One of our direct-hire local guards was killed. We offer our deepest condolences to his family," State Department spokeswoman Victoria Nuland said.
The bomber had struck the first checkpoint on the embassy perimeter.
"The guard who was there, (on) his side of the security barrier was killed, but two who were in that same building, but on the other side of the glass survived," Nuland said.
"We had a Turkish visitor who is in serious condition," Nuland said, adding the visitor was believed to be a well-known Turkish journalist.
Several other people were treated for minor cuts by embassy staff.
Turkish Prime Minister Recep Tayyip Erdogan said the bomber was a member of the Revolutionary People's Liberation Front (DHKP-C), a radical leftwing group blamed for several attacks since the late 1970s including suicide bombings.
The United States was now working with Turkish officials "to make a full assessment of the damage and the casualties, and to begin an investigation," Nuland said.
But she stressed that "the level of security protection at our facility in Ankara ensured that there were not significantly more deaths and injuries."
The attack had taken place "far from the main building" and tightened security upgrades over the years meant more people had not been hurt.
"Let me underscore that the upgrades that we had already done there in Ankara over the last decade resulted in this exterior perimeter that actually saved lives," Nuland said.
The Ankara embassy, which is housed in a building dating back to the 1950s, is due to be fully upgraded. It is among 10 embassies that would benefit if Congress approves a State Department request for increased funds to boost security in the wake of the September attack on the US mission in Benghazi.