The NATO-led force said it would investigate with Afghan authorities claims that its soldiers may have killed three Afghans, including a district chief, after mistaking them for Taliban.

Police in the southern province of Uruzgan said Thursday that the Chora district chief and two of this men had been shot dead by international troops surrounding the home of a friend.

The friend had called him for help thinking that Taliban were outside his door, a provincial police commander, Gulab Khan, said.

"The full details of the incident are not yet known and are currently being established," NATO''s International Security Assistance Force said in a statement late Thursday.

"The Ministry of the Interior and ISAF have agreed to jointly investigate the exact circumstances of the incident and will report their findings when they are available," it said.

The Australian Defence Force said meanwhile that its soldiers may have been involved in the incident.

In a statement late Thursday it said that a special forces patrol group was fired upon from a number of locations and returned fire in self-defence.

It said several groups, including some Afghan National Police, were present during the skirmish.