Two missiles were fired on a hideout of suspected

A suspected U.S. drone strike killed six people in Pakistan's tribal region on Thursday morning, intelligence officials said.

Two missiles were fired on a hideout of suspected militants in an area in North Waziristan, one of seven districts in Pakistan's tribal region bordering Afghanistan.

The intelligence officials asked not to be named because they were not authorized to speak to the media. This is the fourth suspected U.S. drone strike in two days.

On Wednesday, three drone attacks killed 18 suspected militants in Pakistan's tribal region.

While the United States is the only country in the region known to have the ability to launch missiles from drones -- which are controlled remotely -- U.S. officials normally do not comment on suspected drone strikes.