An explosion has rocked a central square in Turkey’s biggest city, Istanbul, Dogan news agency reported, adding that there are casualties at the scene.

The incident reportedly took place on Sultanahmet Square. According to Dogan News, there are a number of people killed and injured at the scene.

Witnesses told local media that police and ambulances have arrived at the site of the blast.

It is not yet clear exactly what caused the explosion.

(RT)