Islamabad, Jan 19 (IANS): At least four people were killed Monday in a drone strike in northwestern Pakistan's tribal region, media reported.

More casualties were feared in the attack that targetted a compound in the Shahi Khel area of North Waziristan's Shawwal tehsil, Dawn reported.

Intelligence sources said the pilotless aircraft fired two missiles at a house believed to be the hideout of suspected militants.

The identity of those killed could not be ascertained.

The area was off-limits to the journalists, making it difficult to independently verify the number and identity of the dead.

Shawal Valley lies on the border of Pakistan's North Waziristan and South Waziristan tribal areas.

Monday's drone strike comes days after seven suspected militants were killed in a similar attack in Shawal area.

North Waziristan is among Pakistan's seven tribal districts near the Afghan border which are rife with insurgents and have been strongholds of Taliban and Al Qaeda operatives, among others.

This is the third drone strike in the country's tribal area since the beginning of this year. Over 21 people have been killed in these strikes in the area.