The attack happened at 9:20 pm (1920 GMT) close to the village of Donja Gusterica, near the town of Lipljan, 30 kilometers (20 miles) east of the capital Pristina.

"Our understanding is that four Finnish peacekeepers were slightly injured by single shot from a shotgun during a routine foot patrol," said Gerry Cooney, spokesman for the peacekeepers in central Kosovo.

"Six persons have been detained and we are searching for the weapon," Cooney added.

He also said that three of the injured were being taken to the largest military installation in Kosovo, Camp Bondsteel that houses over 2,000 US soldiers. One soldier was being being treated locally in the Finnish Camp Ville, in Lipljan.

Cooney said there were no indications as to who might have attacked the troops in the ethnically mixed region in what seems to be the first direct attack upon the force since it came to control the province in June 1999.

Over 17,000 NATO-led peacekeepers known as KFOR are responsible for security in the volatile province that saw an outbreak of ethnic clashes in March when 19 people were killed and over 900 injured.

The violence was the worst of its kind since 1999 as the Albanian majority attacked the Serb minority after unconfirmed reports of Albanian children being chased into a river by local Serbs.

The UN police later said it had no evidence to support claims that Serbs were involved in the death of the children.

NATO however sent some 2,000 reinforcements to quell the violence that lasted for two days and saw some 800 houses burned, 29 churches and monasteries torched and close to 4,000 people, mainly Serbs, displaced from their homes.

Albanian-dominated Kosovo has been under UN and NATO control since 1999 after a military campaign that ended Belgrade's crackdown on the province's ethnic Albanians.

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