KABUL, Afghanistan — Afghan officials say they're trying to determine how an Afghan army soldier who opened fire on Slovakian NATO troops, killing one and wounding six, was able to escape from custody.

Afghan Gen. Abdul Hameed said Monday that suspect Lamber Khan had help from at least one other Afghan soldier in fleeing Sunday morning.

Hameed says the soldier took Khan from detention to a military hospital saying he needed medical attention, and fled with him from there. Authorities are trying to determine if others aided in the escape.

NATO-forces spokesman Brig. Gen. Heinz Feldmann says the coalition has "full confidence" the Afghans will recapture Khan.

The Slovakian soldier killed in Kandahar last week was the ninth NATO service member killed by Afghan forces this year, according to an Associated Press count.