A series of explosives-packed cars and suicide bombs detonated in Ramadi as gunmen stormed a police building in the western Iraqi city on Sunday, police said.

Four car bombs targeting a mosque and police building in the city, 100 kilometres (60 miles) west of Baghdad, were followed by two suicide bomb blasts inside the police building, at which point gunmen stormed the facility triggering clashes, two police officers said.

The officers spoke on condition of anonymity. The number of casualties was not immediately clear.

The first two car bombs exploded at around 11:30 am (0830 GMT) near the Dawlah Kabir Mosque in central Ramadi, followed by a third car bomb also in the city centre.

A short while later, a fourth car bomb went off near a police building in Ramadi, followed quickly thereafter by two suicide bombers blowing themselves up inside the building.

Armed insurgents then stormed the building and clashes were ongoing as of 1:00 pm (1000 GMT), the police officers said.