Iraqi PM Nouri al-Maliki , left, and US Gen. George Casey wave after signing the transfer document,  Sept. 7, 2006

U.S.-led forces began turning over control of Iraq's military to the Shi'ite-led government Thursday, as insurgents unleashed a new wave of deadly attacks.

A ceremony Thursday in Baghdad marked the handover. The top U.S. commander in Iraq, General George Casey, called it an "important milestone" but also said there is still a long way to go.

Iraqi Prime Minister Nouri al-Maliki now has control of one of Iraq's 10 army divisions, as well as its small air force and navy. U.S. officials say the other army divisions will come under control of Iraqi forces perhaps at the rate of two divisions a month.

In violence Thursday, at least 25 people were killed in attacks across Iraq. The deadliest one killed at least 10 people at a Baghdad gas station used by police.

Meanwhile, the Arabic television network Al-Jazeera aired an audiotape that it said was from the leader of al-Qaida in Iraq, Abu Hamza al-Muhajer. The speaker on the tape called on all insurgents in Iraq to unite.

And the U.S. military said two U.S. soldiers were killed in separate incidents Wednesday, and a Marine died Thursday from wounds sustained the day before.