At least six people were killed in a suspected U.S. drone strike in northwest Pakistan's South Waziristan tribal agency bordering Afghanistan, local TV channels reported Thursday.

According to the private Express News, the pilotless aircraft fired two missiles to a house at Kani Kuram village in South Waziristan, killing at least six people and injuring nine others. The private channel Geo News said the attack has killed eight.

This is the fourth drone attack in less than a month in the same region. Pakistan's most wanted Taliban chief, Baitullah Mehsud, has been confirmed killed by a U.S. missile attack on Aug. 5 in South Waziristan, part of the lawless tribal regions along Pakistan's border with Afghanistan. Taliban and Al-Qaeda leaders are believed to be hiding in the area.

U.S. drones regularly fire missile in the Pakistani tribal regions to target the militants and opposition parties say Pakistani government permits such attacks. But Pakistan government denies the charges.

Pakistani officials say the drone strikes have killed more than 400 people in more than 40 attacks since August 2008.

Pakistan insists that drone attacks are counterproductive and must be stopped but the CIA chief and top U.S. officials have ruled out any change in the policy.

Pakistani forces are on an offensive against the Taliban in South Waziristan against Taliban sympathizers after it launched an assault in the Swat Valley and Buner in the northwest in April.

(Xinhua News Agency August 27, 2009)