Hamid Karzai's statement issued Monday says the Afghan intelligence service determined that a NATO rocket hit Regi village in Helmand province's Sangin district. The dead included women and children. Karzai condemned the attack.
But NATO spokesman Col. Wayne Shanks says initial reporting from the area did not confirm any civilian casualties or NATO rockets gone astray.
Special Report: Afghanistan
He said insurgents and NATO forces fought Friday in an area about 4.3 to 5 miles away but there was no evidence in initial reporting that it was connected to the claims of rocket fire in Regi.
Allegations come in the wake of the leak of 91,000 classified U.S. records on the Afghanistan war by the whistle-blower website Wikileaks.org is one of the largest unauthorized disclosures in military history.
More on the WikiLeaks release:
WikiLeaks Founder: Many More Documents to Come
WikiLeaks: Evidence of War Crimes in Afghan Docs
Afghan Gov't "Shocked" by Leak of War Documents
Analyst: WikiLeaks Report Fuels War Debate
WikiLeaks Reveals Grim Afghan War Realities
Report: Pakistan Aiding Afghan Insurgency
Papers: Leaks Show Unreported Afghan Deaths
The documents cover much of what the public already knows about the troubled nine-year conflict: U.S. spec-ops forces have targeted militants without trial, Afghans have been killed by accident, and U.S. officials have been infuriated by alleged Pakistani intelligence cooperation with the very insurgent groups bent on killing Americans.
WikiLeaks posted the documents Sunday.
The release was instantly condemned by U.S. and Pakistani officials as both potentially harmful and irrelevant.
Pakistan's Ambassador Husain Haqqani has stated the documents "do not reflect the current on-ground realities," in which his country and Washington are "jointly endeavoring to defeat al Qaeda and its Taliban allies."