An explosion rocked central Istanbul's Sultanahmet square, a major tourist attraction, on Tuesday. Istanbul governor's office says 10 killed, 15 wounded in Sultanahmet explosion, statement on website.
The cause of the explosion was not immediately clear.
A number of policemen were sent to the scene as police sealed off the Hippodrome area of historic Sultanahmet after an explosion that could be heard from several districts of Istanbul.
All transportation in the area, including trams, has been halted. Ambulances and police have arrived to seal off the area and tend to the wounded.