Istanbul - Turkish Prime Minister Ahmet Davutoglu on Tuesday blamed ISIS for the suicide attack on tourists in Istanbul.
Ten people - 9 of them Germans - died in the attack.
The attacker is said to have links to Syria.
The large blast, which could be heard several kilometres away, took place at around 10:15 (08:15 GMT) in the Sultanahmet area, which is home to the Hagia Sophia museum and the Blue Mosque, both major tourist attractions on the European side of the metropolis.
The largest blast in the country's history took place in October, in Ankara. Two suicide bombers blew themselves up near a train station during a pro-Kurdish peace rally, killing 100 people.