BAGHDAD – Al-Qaida is rebuilding in Iraq and has set up training camps for insurgents in the nation's western deserts as the extremist group seizes on regional instability and government security failures to regain strength, officials say.

Iraq has seen a jump in al-Qaida attacks over the last 10 weeks, and officials believe most of the fighters are former prisoners who have either escaped from jail or were released by Iraqi authorities for lack of evidence after the U.S. military withdrawal last December. Many are said to be Saudi or from Sunni-dominated Gulf states.

During the war and its aftermath, U.S. forces, joined by allied Sunni groups and later by Iraqi counterterror forces, managed to beat back al-Qaida's Iraqi branch.