A Swedish non-government organization says two patients and a caretaker were killed during an overnight raid by Afghan forces on one of its clinics in Wardak province.

Jorgen Holmstrom, country manager for the Swedish Committee for Afghanistan, said Thursday there is indication the attack was carried out by the Afghan National Army, condemning it as a "gross violation of humanitarian principles and the Geneva Convention."

Holmstrom says his organization has worked in Afghanistan since 1980 as "a neutral party" and that all three victims were Afghan citizens.

A Wardak official, Akhtar Mohammad Tahiri, confirmed that Afghan special forces conducted the raid on the Swedish clinic in Tangi Saidain district, insisting the three killed were members of the Taliban.

He says two people were also wounded in the raid.