The U.S. military has released a Shiite insurgent believed to have plotted an ambush in Karbala in 2007 that killed five U.S. soldiers, according to media reports Tuesday.

The release of Laith al-Khazali on Sunday is both part of a larger reconciliation effort in Iraq and involves the freeing of British hostages who are being held by the militant group Asa’ib al-Haq, according to the British Broadcasting Corp. News Web site.

U.S. officials refused to confirm any link between Khazali’s release and the hostages.

Members of the militant Shiite group Asa’ib al-Haq captured a British computer expert and his four bodyguards when they were working in the Iraqi Finance Ministry in Baghdad in May 2007.

U.S. and British officials say al-Khazali’s release is part of a greater reconciliation effort between the Iraqi government and the group, The New York Times reported

In return, Asa’ib al-Haq has adopted an unconditional cease-fire, Lt. Col. Brian Maka, a U.S. military spokesman, was quoted as saying in the Times.

"Asa’ib al-Haq has pledged to representatives of the Iraqi prime minister to give up violence and move the group towards peaceful integration into Iraqi society," Maka said.

Khazali and his brother were accused of planning a raid in Karbala on Jan. 20, 2007, that led to the deaths of five U.S. soldiers.

Militants dressed in U.S. Army-style combat uniforms attacked a provincial security building where the soldiers and Iraqi troops were discussing protection for religious pilgrims.

Four of the five U.S. soldiers were fatally shot after they were captured, handcuffed and driven miles away to Babil province, U.S. and Iraqi officials said at the time.

Qais al-Khazali, Asa’ib al-Haq’s leader, remains in American custody, the Times reported.

American officials have alleged that the group is supported by Iran, which has long been alleged by the Americans to harbor and train Shiite militias the military calls "special groups."

The Times reported that Laith al-Khazali was released Sunday, and followers picked him up at Baghdad’s Green Zone and took him to Sadr City.