The New York Times reports private security guards working for Blackwater participated in CIA "snatch and grab" raids against suspected insurgents in Iraq and Afghanistan.
A U.S. official confirms to The Associated Press that Blackwater provided security and moved around with CIA teams on missions in war zones, but denies they performed CIA missions.
The CIA says the spy agency "uses contractors in roles that complement and enhance the skills of" its work force.
Blackwater changed its corporate name to Xe Services after a series of controversies, including the September 2007 shooting in Baghdad by five of its guards that left 17 civilians dead.
The report comes as the House Intelligence Committee investigates the CIA's hiring of Blackwater to be part of a program to kill or capture al-Qaida leaders.