Turkish police on Thursday detained the suspected driver of the car used in an attack on the U.S. consulate in Istanbul this week, in which 6 people were killed, media reports said.
The car had also been seized and the driver was being questioned at police headquarters, CNN Turk reported.
Earlier in the day, police detained four other suspects.
Interior Minister Besir Atalay described the incident on Wednesday, in which three policemen and three gunmen were killed, as a suicide attack.
It came amid rising tensions in Turkey, with the ruling party under threat of being banned for alleged anti-secular activities and police investigating a shadowy far-right group suspected of plotting a military coup.
Security was tightened around Istanbul's diplomatic missions and busloads of police were stationed at the site of the attack outside the high-walled consulate, where the U.S. flag flew at half-mast.
Police were investigating whether al Qaeda was behind the attack. Newspapers reported that the gunmen who carried it out had received weapons training in Afghanistan.
Atalay said only one gunman seemed to have traveled abroad.
Some security experts were skeptical about an al Qaeda link, given the small scale and amateurish nature of the attack.
DEAD POLICE MOURNED
At the official funeral ceremony at police headquarters in Istanbul, lines of police and officials said prayers in front of the three officers' coffins, draped in Turkish flags.
"We saw once more that terror is ruthless, has no religion, faith or nationality. We condemn terrorism from wherever it comes," Atalay said.
Turkey has seen violent attacks from a variety of groups in recent years, including leftist, Kurdish and Islamist militants.
The most serious were in November 2003 when 62 people were killed by Islamists who struck at two synagogues, a bank and the British consulate in Istanbul.
The U.S. consulate had been moved to a more secure location in Istanbul following the Sept. 11 al Qaeda attacks in New York.
A father of one of the gunmen had spent three months in prison after being detained as part of an investigation into the Turkish Islamist militant group Hizbullah, CNN Turk said.
The three gunmen had lived in the same Istanbul district and one of them had recently completed his military service.
In Turkey's eastern Igdir province, friends and relatives of one of the dead gunmen, named as Bulent Cinar, expressed shock at his involvement, Anatolian said.
"Bulent was a good boy. We were shocked when we heard what happened. I can't understand how he could do such a thing," said Erhan Karaboga, a friend of his.
(Editing by Stephen Weeks)
