One person was killed and 11 were injured in an explosion in the northern part of Mitrovica in Kosovo on Friday morning, Serbian and Kosovo media said.
It is unknown who activated the hand grenade which exploded shortly before 10 am as hundreds of Serbs were protesting against the Kosovo government's intention to open an office for the issue of personal identification documents.
The town is calm and the protests ended. The government premises are being secured by the police of the European judicial mission EULEX.
The blast prompted Serbian President Boris Tadic to convene a session of the National Security Council. He asked international institutions to respond in the strongest terms and preserve law and order in Kosovo, adding such acts of provocation threatened regional stability and that Serbia would not respond.
Serbian Prime Minister Mirko Cvetkovic condemned the explosion in the strongest terms.
EULEX said it deployed two special police platoons to back up the Kosovo police in securing the area where the blast took place.
The mission extended condolences to the family of the casualty and sympathy to those injured, saying in a press release it deplored the explosion and all other violent acts, while encouraging all sides to remain calm and avoid actions that might escalate the situation.
It has yet to be established who threw the grenade and from where, EULEX said, adding the Kosovo police were investigating the case.