WANA, Pakistan (Reuters) - A suspected U.S. missile strike on a Pakistani madrasa near the Afghan border killed six people on Monday, possibly including an al Qaeda chemical and biological weapons expert, Pakistani security officials said.
A senior Pakistani security official said Abu Khabab al-Masri, an Egyptian chemist regarded as one of al Qaeda's top bomb makers, could have been the target.
Monday's pre-dawn attack blitzed a house close to a madrasa used by militants near Azam Warsak village, about 20 km (12 miles) west of Wana, the main town of the South Waziristan tribal region, a known hotbed of Taliban and al Qaeda support.
"We have heard that Abu Khabab al-Masri might have been killed in the strike but there's no confirmation as nobody could go there," a security official, who declined to be identified, told Reuters.
The 55-year-old al-Masri has a $5 million U.S. bounty on his head, and there have been reports of him being killed before.
The attack, one of many in recent months, was launched hours before Pakistani Prime Minister Yousaf Raza Gilani was due to meet President George W. Bush in Washington for talks that will focus on the conduct of the war against terrorism.
The United States, alarmed by rising casualties among Western forces in Afghanistan, wants Pakistan to do more to contain the al Qaeda and Taliban threat in its territory.
Several drone missile attacks have been carried out this year by U.S. forces against militants linked to al Qaeda and Taliban hiding in the northwest tribal lands near the Afghan border.
One official told Reuters the madrasa, or religious school, struck on Monday was a militant base and the owner of the targeted house, a tribesman named Malik Sallat Khan, had ties with the militants.
"The owner of the house and seminary had some links with militants, and the madrasa was not used for education, but as a compound," he said.
Another official, who also declined to be identified, said at least three missiles hit the house and seminary, killing six people, including foreigners, and wounded three others.
Residents said they heard the sound of a drone aircraft engine, suggesting that the missile may have been fired by a U.S.-controlled unmanned Predator.
"We had heard the sound of a drone engine just before the explosions," said Zia-ur-Rehman, a local tribesmen.
"These drones have been flying since late Sunday night."
Spokesmen for NATO and U.S.-led coalition forces in Afghanistan denied involvement in any cross-border strike, but could not speak for the CIA, which also operates drones.
Pakistan's military spokesman said he had little information, and noted that U.S. coalition forces were no longer informing the Pakistan army about every missile strike.
"Some incident did take place but what kind of strike it was, whether it was missile or rocket attack or bomb explosion, we don't know," said Major General Athar Abbas.
"Coalition forces don't share information about any strike with us prior to any attack," he said.
Chairman of Pakistan's Joint Chiefs of Staff Committee General Tariq Majid warned that crossborder strikes could damage relations with the United States during a meeting with U.S. CENTCOM acting commander Lieutenant General Martin E Dempsey at army headquarters in Rawalpindi.
"Our sovereignty and territorial integrity must be respected, any violation in this regard could be detrimental to bilateral relations," a military statement quoted Majid as saying.
Security in northwest Pakistan has deteriorated in the past few weeks after a lull that followed the formation of a new government in March following elections in February.
Gilani's government embarked on a strategy of dialogue with militants, although there has been limited military action in some parts of the tribal region where unrest has flared.
Western governments fear the Pakistani strategy provided the militants with breathing space to increase the flow of fighters across the border to fuel the Afghan insurgency.
(Additional reporting by Mohammad Hashim, Haji Mujtaba, Alamghir Bitani and Hafiz Wazir)
(Writing by Kamran Haider; Editing by Simon Cameron-Moore and Valerie Lee)
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