At least seventeen people were killed in the attack on the government compound in Ramadi [Reuters]

At least 17 people have been killed, including 5 policemen, and 50 others wounded after twin suicide bombings struck a government compound in Iraq's western city of Ramadi, officials say.

It was the second attack this month on the compound, which houses the provincial council and the police headquarters for Anbar province.

"The death toll is 17 killed and between 50 and 60 wounded," Hussein Kamal, the deputy interior minister, told the Reuters news agency.

Qassim Mohammed, Anbar's governor, said the first blast happened when a minibus exploded outside the compound and the second was caused by a suicide bomber on foot, disguised as a policeman.

"Prime Minister (Nuri al-Maliki) has ordered an investigative committee to be formed due to the repeated targeting of (this) building in Anbar province," Kamal said.

Ramadi hospital's emergency room was reportedly filled with patients wounded in the attack.

The hospital was also crowded with people who had responded to an appeal broadcast on mosque loudspeakers to donate blood to help the injured.

'Al-Qaeda attack'

Hikmet Khalaf, the deputy governor of Anbar, blamed the attack on al-Qaeda fighters.

"The goal of al-Qaeda is clear, to strike at security in the province. This is not the first attack targeting the local government buildings.

"The attackers chose a crowded intersection in Ramadi to kill large numbers of civilians who were headed to the government buildings," he told Reuters.

Earlier this month, Iraqi security forces arrested 39 al-Qaeda militants, including the group's leadership in Anbar province and one of its top officers in Iraq.

"The arrest of senior al-Qaeda leaders in Anbar ... a month ago does not mean that al-Qaeda has ended because al-Qaeda has the ability to organise itself in a short period," Kamal said.

"We were expecting such attacks from al-Qaeda, not just in Anbar but in all of Iraq, to prove its presence at this stage, especially after the formation of a new government, to make the security forces look helpless, weak and like a failure."

Iraq formed a new government last week after months of factional squabbling, subduing fears that insurgents could exploit the political vacuum to destabilise the country.

The last attack on the government compound in Ramadi happened on Dec 12, when a suicide car bomber killed 13 people and wounded dozens. In December 2009, twin suicide blasts killed at least 24 and wounded more than 100 just outside the provincial government headquarters.

While overall violence in Iraq has dropped from the peak of sectarian warfare in 2006-7, bombings and attacks still occur almost daily.