In recent years the Pakistani media has asserted that Blackwater was responsible for numerous terrorist attacks in the restive western areas of the country -- attacks attributed by the Pakistani and American governments to the Taliban, al Qaeda and other militant Islamic groups.
According to the intelligence consultant, Blackwater personnel have worked for the CIA in Pakistan since at least 2004, most as security guards, but some as paramilitary operatives working to target militants in the country's tribal regions.
The Pakistani men Davis shot on Jan. 27 were carrying pistols and stolen cell phones, according to the Lahore police. Pakistani government officials have told ABC News that the two were working for that country's intelligence agency, Inter-Service Intelligence, and were also conducting surveillance. But the police report records interviews with two witnesses who say that they had been robbed earlier by the two men Davis shot, and American officials deny that the two men worked for the ISI.
"We have no information to suggest Davis was being followed by the ISI," one current U.S. official said.
ABC News' Lee Ferran and Nick Schifrin contributed to his report.