A bomb in a cafe has killed least one person and prompted Turkish police to step up security measures across Ankara.
Police said the bomb exploded in the three-story cafe in Ankara's commercial district, Kizilay, at mid-morning. Authorities said they were investigating into whether this was a suicide bomb attack.
They said a young woman suspected of carrying the explosive device was killed in the blast, which wounded at least one other person, a woman.
The cafe, called the Crocodile, is frequented by university students. It was badly damaged in the explosion, which is believed to have occurred in the café's restroom. Twisted metal and shattered glass were scattered next to a busy street.
Police said it remained unclear immediately whether the blast was triggered as the bomber was seeking to plant the device. Eyewitnesses said they saw a young woman entering the toilet area shortly before the explosion.
Only a few customers were in the cafe when the bomb went off. The area was quickly cordoned off by police as they sought to gather evidence.
Western diplomats in Ankara said they had been warned of a possible attack on Monday, a national holiday to mark youth and sports day. But the Crocodile was not frequented by foreigners, and police speculated that the likelihood of a suicide attack was low, given that the bomber had not selected a crowded area, a typical target for suicide bombers.
The cafe's owners said they had not received any threats prior to the attack.
Extreme left-wing groups, religious fanatics, and Kurdish separatist groups have staged bomb attacks against civilians as well as against western tourists and diplomats in Turkey in the past.