An explosion has been heard at Istanbul’s Bayrampasa metro station, with reports of at least one injury.
The mayor of the district where the blast happened said it had been caused by a bomb on an overpass near the station.
Images shared on social media appeared to show people walking near train tracks after trains were stopped.
Authorities suspended services on the city’s metro network following the blasts.
Initial reports said the explosion had been heard in several different parts of the city.
Emergency services made their way to the scene of the blast, which occurred at about 17:15 local time (15:15 GMT).
Eyewitness Onur Dugenci said he was close to the station when he heard “a very, very loud bang”.
“Later, my family and friends called from other parts of the city and said they could hear it, too,” Mr Dugenci said.
“There was no fire. But the explosion was so powerful that the windows on some cars were broken,” he continued.