Media reports say last week's missile attack in Pakistan killed at least three al-Qaida leaders, including one of the terror group's top chemical weapons experts.
U.S. news reports say Pakistani officials have identified one of those killed as Midhat Mursi, an Egyptian also known as Abu Khabab al-Masri.
Security experts describe Mursi as a senior al-Qaida commander and the terror group's chemical and biological weapons expert.
Mursi allegedly ran al-Qaida's Derunta training camp in Afghanistan and produced rough textbooks on how to create weapons of mass destruction.
He is on a U.S. list of most-wanted terror suspects, with a $5 million bounty for his capture.
There has been no official confirmation of the reports from either the Pakistani or the U.S. governments.
Thursday, Pakistani Information Minister Sheikh Rashid Ahmed acknowledged that foreigners were killed in the attack on a remote border town, but says local supporters removed their bodies.
"These militants took their bodies and we are investigating. We are getting information about who they are," he said.
According to news reports, the U.S. missile attack targeted al-Qaida's deputy commander, Ayman al-Zawahiri, who was expected to attend a dinner in the village on the night of the attack.
Local officials say Zawahiri likely failed to appear and so escaped injury.
But unnamed Pakistani officials are widely reported as claiming Mursi and two other senior al-Qaida commanders died in the attack, including Zawahiri's Moroccan son-in-law.
Also among those reportedly killed was Abu Obaidah al-Misri, the chief of insurgent operations in neighboring Kunar province in Afghanistan.
The air strike killed 18 civilians, including a number of women and children, sparking widespread anti-American protests throughout the country. On Thursday, more than a thousand people in western Pakistan joined a rally led by Islamic political groups.
Pakistani political analyst Hassan Askari says the new reports are unlikely to stop the protests or influence hardcore anti-American sentiment.
"Their attitude is not expected to change. However, others who are not really part of the Islamic political parties or militant groups, their opinion will definitely be softened by this information," he said.
Pakistan lodged a formal complaint over the attack with the U.S. ambassador in Islamabad.
And Prime Minister Shaukat Aziz says he will pursue the matter during a meeting in Washington with President Bush next week.
The United States has not confirmed the attack but U.S. Secretary of State Condoleezza Rice has promised to address Pakistani concerns about it.