Security officials in Pakistan say a U.S. drone strike has killed at least five militants in the country's northwestern tribal district.

Authorities say four missiles were fired into a village Sunday near the Afghan border. Officials say the strike targeted the home of a militant commander.

On Saturday, a drone strike in the same region killed at least two insurgents.

Drone strikes have become an increasingly contentious issue between Washington and Islamabad, following a November strike that killed 24 Pakistani soldiers.

Pakistan has demanded the U.S. apologize for the November air strike. Washington has refused.

Pakistan says the missile attacks are counter-productive, violate its sovereignty, kill civilians and fuel anti-U.S. sentiment.