Baghdad - Al-Qaida in Iraq claimed responsibility for twin suicide bombings against its former insurgent allies that killed almost 50 people and said in an Internet statement posted Friday that it hoped the attacks would inspire others to "martyrdom."

Al-Qaida's ability to operate in Iraq has been sharply curtailed over the past couple of years because of a dramatic security crackdown, but attacks like the July 18 bombings have shown it remains able to strike back.

In another setback in their battle with the group, Iraqi officials disclosed Thursday that four suspected al-Qaida members had escaped from a prison that the U.S. had handed over to Iraq a week earlier.

In its Internet statement, al-Qaida said the bombings a week ago were part of a series of attacks against its turncoat allies - former Sunni insurgents who are now members of pro-government militias known as Awakening Councils.

It described its targets as "leaders of apostasy and the hypocritical Awakening." One of the attacks, it said, targeted the Sunni fighters as they "rushed to get the crumbs for which they have sold their religion."

The fighters were waiting at a Baghdad military checkpoint to collect their government paychecks when the bomber struck, killing 40. Al-Qaida put the number of dead and wounded at 120.

It said the other attack by one of its "lions" was at an Awakening Council headquarters in the western city of Qaim, a former insurgent stronghold near the Syrian border. It claimed that bombing killed or wounded 20.

The official death toll was three dead and six wounded.