At least nine people have been killed and more than a dozen injured in multiple bomb attacks in the city of Ramadi in western Iraq's Anbar province, military and interior ministry sources have said.

Police said on Thursday that two improvised explosive devices [IED] exploded near the eastern gate of a local government building compound one after the other.

Al Jazeera's Omar al-Saleh reporting from Baghdad, quoting government sources said: "Significantly, the compound houses governor, police command and several other security directorates."

Shortly afterwards a car bomb was detonated nearby by the vehicle's driver.

A fourth bomb, also a suicide car bomb, went off near the Ramadi hospital where military and civilian rescuers were rushing to bring the victims for treatment, Hikmet Khalaf, Anbar province deputy governor told Reuters.

'Al-Qaeda behind attacks'

"Al-Qaeda is behind these attacks. They always carry out multiple explosions to inflict as heavy casualties as possible on the security forces and civilians," Khalaf added.

"The four explosions took place between eight and 8:30pm local time, and most of the people at this time were at home and the casualties might have been higher if the explosions took place earlier,'' Jasim al-Halbusi, head of the Anbar Provincial Council, said.

The sprawling desert province of Anbar was the heartland of Sunni militia operations after the 2003 US-led invasion.

Its main cities, Ramadi and Falluja, witnessed some of the fiercest fighting of the war.

While overall violence in Iraq has dropped from the height of sectarian warfare in 2006-7, bombings still occur daily and insurgents are still capable of carrying out lethal attacks almost eight years after the US-led invasion.

In February, a suicide bomber blew himself up during a ceremony in a cultural centre in Ramadi, killing 15 people and wounding 21.