ISLAMABAD: A suspected U.S. drone strike on a militant hideout in northwestern Pakistan killed six men, Pakistani intelligence officials said Wednesday.

In a separate incident, gunmen ambushed a police patrol Wednesday in the northwestern city of Peshawar, killing three police officers and wounding six, said local police official Saeed Khan. No one claimed the attack.

The two intelligence officials said the compound hit late Tuesday in the Shawal area of North Waziristan belonged to Islamic militants loyal to an Afghan warlord and was also frequented by Uzbek fighters. The officials say the identity of those killed has not yet been determined. They spoke on condition of anonymity because they were not authorized to talk to the media.

The Pakistani military has been battling militants in Shawal as part of an offensive launched in June 2014 in North Waziristan, a longtime stronghold of al-Qaida and other armed groups along the Afghan border.

Pakistani military courts have meanwhile convicted and sentenced five Islamic militants to death over a series of attacks, the army said in a statement Wednesday. It said a sixth convicted militant was sentenced to life in prison.

The military said the convicts were involved in a jail break, sectarian attacks and the killing of polio workers. It said three belonged to the Pakistani Taliban and three to allied militant groups. The army said the trials were fair and that the men can appeal their convictions.

Pakistan's parliament voted to allow military courts to try civilians in terrorism cases after last year's Taliban attack on a school in Peshawar, which killed some 150 people, mostly students.