Seven suspected militants were killed and several others were injured Saturday night in a U.S. drone strike in northwestern Pakistan, two Pakistani intelligence officials told CNN.

The officials said the drone fired several missiles at a suspected militant hideout in Machi Khel, a village in North Waziristan, one of seven districts in Pakistan's ungoverned tribal region.

The area is widely believed to be a stronghold of the Pakistani Taliban, the Afghan Taliban and al Qaeda-linked militant groups that are fueling the insurgency across the border in Afghanistan.

Based on a CNN count, all of the 28 U.S. drone strikes this year have hit locations in North Waziristan and its border with South Waziristan. The officials asked not to be named because they are not authorized to speak to the media.

The United States does not comment on drone activity, which has caused tension between Washington and Islamabad in the past.