PHOTO: AFP
The huge blast caused panic close to the metro station in the Bayrampasa district of Istanbul and injured at least six people, NTV television said.
PHOTO: AFPTurkey arrests 50 foreigners in Ankara blasts probe
NTV said it may have been caused by a bomb while other reports said the cause could be linked to an electrical transformer.
"The cause of the explosion is not clear. We are investigating all possibilities," Istanbul governor Vasip Sahin was quoted as saying by the state-run Anatolia news agency.
PHOTO: AFPLarge numbers of ambulances were despatched to the scene, as commuters were helped to safety, reports said.
"Metro services have been halted after a sound similar to an explosion was heard, its cause remains unknown," the Istanbul municipality said in a statement.
Four held in Turkey over Ankara attack, bomber identified
PHOTO: AFPTurkey is currently on alert for attacks after 103 people were killed on October 10 when two suicide bombers ripped through a crowd of peace activists in the capital Ankara, the worst attack in modern Turkey's history.
COMMENTS
Comments are moderated and generally will be posted if they are on-topic and not abusive.
For more information, please see our Comments FAQ