Also known as Midhat Mursi, he specialized in chemical and biological weapons and once conducted nerve gas tests on tethered dogs.
The strike also may have killed al Qaeda's chief of operations for Afghanistan and Pakistan and another chief of operations for Afghanistan's Konar province.
A Pakistani intelligence official, speaking to the Associated Press on condition of anonymity because he's not authorized to speak to journalists, said authorities still did not know the names of the dead foreign militants but suspect one was a ranking al Qaeda figure.
"We have no names. We know one of them had value in al Qaeda. He had intelligence value in the network, but we are still checking his name," said the official.
However, Pakistani Interior Minister Aftab Sherpao told AP the government does not know the identities of the foreigners believed killed in the missile strike Friday, which officials have said targeted Osama bin Laden's top aide, Ayman al-Zawahri.
"We are still investigating. There's a possibility that some foreigners were there, but we still do not know," said Sherpao, who was in New York with visiting Prime Minister Shaukat Aziz.
Sherpao said the government had not retrieved the bodies of any of the four foreign militants reported killed in the raid. He said the bodies may have been taken by a local pro-Taliban cleric, Maulana Faqir Mohammed, who also is being hunted by authorities.
Martin reports that the reported deaths would not cause al Qaeda to collapse, but it would seriously damage the network's command structure. U.S. officials say al Qaeda command has been using the remote Pakistan frontier as a sanctuary from which to plan and launch operations.
Pakistan has recently sent its own army to clear foreign fighters out of the border area, but U.S. intelligence concluded the operations were making little headway. So, in recent weeks the CIA has opened a new campaign of airstrikes by unmanned drones whenever it gets reliable intelligence on the whereabouts of al Qaeda leaders, Martin reports.
The U.S. government will not officially confirm these CIA airstrikes are even taking place, Martin added, and the Pakistani government files protests against them, even though they are conducted with Pakistani approval.