Five people were injured when a pipe bomb exploded on an overpass near an Istanbul metro station, the district mayor has said.
Atilla Aydıner, the mayor of the Bayrampaşa district on the European side of the city, was speaking on live television after the explosion hit the industrial and residential area during the evening rush hour on Tuesday.
CCTV footage showed the blast as traffic drove past.
Large numbers of ambulances were despatched to the scene, as commuters were helped to safety. There was panic close to the metro station, NTV television said.
The Istanbul municipality said that metro services were halted after the explosion. Earlier reports had said it could be linked to an electrical transformer.
Turkey is on alert for attacks after 103 people were killed on 10 October when two suicide bombers targeted a march of pro-Kurdish peace activists in the capital, Ankara, in the worst attack in modern Turkey’s history.