An assailant armed with an explosive device attacked a police station in Istanbul's historic Sultan Ahmet district on Tuesday injuring at least one police officer, Turkish television stations reported.
A CNN Turk reporter said police exchanged fire with the attacker, while broadcaster NTV said the assailant had detonated a hand grenade. Television footage showed police sealing off streets, and public transport in the area shut down.
There was no immediate claim of responsibility but the attack comes less than a week after far-left group DHKP-C said it was behind a grenade attack on police near the prime minister's office in Istanbul.
The DHKP-C (Revolutionary People's Liberation Party-Front) was also behind a suicide bombing at the U.S. Embassy last year as well as attacks on Turkish police stations.
Sultan Ahmet lies on Istanbul's historic peninsula, home to the Blue Mosque and Aya Sofya museum, and is among the world's most visited tourist destinations.