Update 2 | Four detained for questioning over deadly car bomb attack in Istanbul

Turkish media is reporting that four men have been detained in relation to an explosion that hit the central Istanbul district of Vezneciler, killing 11 people and injuring at least 36 others.

The blast struck near a bus stop near the city's historic Bayezit Square neighbourhood, a major tourist attraction, on Tuesday morning, with many ambulances seen in the area.

Turkish media say a police bus was the blast’s central target.

The explosion reportedly occurred when a remote-controlled device was detonated during the morning rush hour, as a police vehicle was passing the area, according to broadcaster NTV.

Pictures showed the wreckage of a bus destroyed and the facade of nearby buildings damaged.

No group claimed responsibility immediately but groups including Deash and Kurdish separatists have carried out bombings in the past few years.