PRISTINA, Serbia-Montenegro -- One Serb was killed and four others injured in a bomb explosion at the weekend in eastern Kosovo, a United Nations official said on Monday.

The bomb exploded on Sunday afternoon outside a shop in Cernica, around 35 kilometers (22 miles) east of the provincial capital Pristina, UN mission spokesman Andrea Angeli said.

"Milomir Savic, 35, died during the night and the others are still being treated," Angeli said.

The village of Cernica is an ethnically mixed Serb-Albanian sector of the province, controlled by a U.S. contingent of NATO-led peacekeepers.

Kosovo technically remains a province of Serbia but it has been under UN administration since 1999, when a NATO bombing campaign ended a two-year war between Serbian security forces and ethnic Albanian separatists.

UN police said they believed a hand grenade was the cause of Sunday's explosion, AFP reported.

Barry Fletcher, spokesman for the UN police in Kosovo, said the attack could have been motivated by ethnic hatred but he declined to rule out other possibilities, saying the investigation was in its early stages.

"It is possible it could be an ethnically motivated attack but we were not able to interview the victims yet and we have no suspects so far," Fletcher said. Tensions are on the rise between the Kosovo's ethnic Albanian majority and its Serb minority following a spate of attacks on the province's Serb community.

Last month two Serb youths were gunned down while swimming in a river in western Kosovo, in what was feared to be a hate crime. A third Serb died in hospital after a separate attack.

The tensions have been aggravated by the Serbian Parliament's adoption of a declaration affirming Belgrade's sovereignty over Kosovo.

The new head of the UN mission in Kosovo, former Finnish prime minister Harri Holkeri, said on Saturday Kosovo's final status would be up to the United Nations to decide.

"The final status of Kosovo will be decided by the UN Security Council based on resolution 1244," Harri Holkeri told reporters in Ohrid, western Macedonia.

Passed by the UN Security Council in June 1999, Resolution 1244 put an end to 18 months of clashes between the Serb regular army and the ethnic Albanian separatists of the Kosovo Liberation Army.

"We are trying to find a solution through dialogue on practical issues, which may help the Security Council to make headway toward a final status (for Kosovo)," Holkeri said.