A bus carrying riot police official was struck by a bomb in Istanbul on Tuesday, wounding at least five police officers, news reports said.

Eleven people including seven police officers were killed in the attack, the governor said.

"Seven police and four citizens lost their lives," Vasip Sahin told reporters at the scene. Thirty-six people were injured.

The blast occurred at a busy intersection near an Istanbul University building in the city's Beyazit district during the morning rush hour.

The state-run Anadolu Agency said several ambulances were sent to the scene.

Dogan News Agency said the bomb was placed inside a car parked on the side of a road and detonated as the police bus was passing by. There was no official confirmation of the report.

The police bus was overturned from the force of the blast which also damaged nearby buildings, including a hotel whose entrance appeared gutted and windows were blown out. Several cars were also wrecked.

There was no immediate responsibility claim.

The rebels of the Kurdistan Workers' Party, or PKK, have been targeting police and military personnel with bombs since July, when a fragile peace process between the rebels and the government collapsed. The Islamic State group has also been blamed for a series of deadly bombings in Turkey.

An estimated 500 Turkish security personnel have been killed in attacks or in conflict with the Kurdish rebels, according to the military, which claims to have killed 4,900 PKK militants in operations in Turkey and northern Iraq, where the group has a major bastion. Turkish warplanes regularly raid PKK bases in northern Iraq.

Last Update: Wednesday, 20 May 2020 KSA 13:58 - GMT 10:58