A female suicide bomber has blown herself up in the Turkish city of Istanbul, killing at least one police officer and injuring another, media reported.
According to Istanbul governor Vasip Sahin, the attacker's nationality and identity remained unknown, BBC reported citing Turkish TV.
She targeted a police station in the tourist hub of Sultanahmet, near the Blue Mosque and Hagia Sophia museum, BBC reported.
No group has yet claimed responsibility for the attack, the second on police in a week.
A man who threw grenades and fired at the police near the prime minister's office last Thursday was arrested, but no-one was injured in that attack.
The bomber in the latest incident died in the attack.
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Police sealed off an area in the historic district, where the Blue Mosque and the Hagia Sophia museum are located.
Sahin said the woman entered the police station said she lost her wallet before detonating the bomb.
The attack briefly shut down public transport around the historic Sultanahmet square, a popular tourist destination visited by thousands of people every day.
The banned Marxist DHKP-C group said it was behind the earlier attack in the city Jan 1, which took place outside Dolmabahce Palace.
Considered a terrorist organisation by Turkey, the EU and US, DHKP-C has launched several attacks since the 1980s, including on police, security officials and, most recently, the US embassy in Ankara in 2013.
Turkey is on high alert - and the latest incident is a stark reminder of the many security challenges that this country must now confront.
Indo-Asian News Service
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