In a renewed bout of violence, hundreds of Serbs broke on March 14 into a United Nations courthouse Kosovska Mitrovica, in the northern part of the province, and hoisted the Serbian flag on it, replacing the UN one, the International Herald Tribune reported.

The move comes on the same day that Nato secretary general Jaap de Hoop Scheffer is visiting Kosovo's capital Prishtina. It also comes on the heels of daily protests outside the court ever since Kosovo declared independence.

The UN police force did not resist to the move and most of the protesters left the building later in the day. The chief of the UN mission in Kosovo (UNMIK), Joachim Ruecker, called on police to regain control of the courthouse.

“Those who turned to violence in North Mitrovica have crossed one of UNMIK's red lines. This is completely unacceptable,” Ruecker said in a statement, as quoted by International Herald Tribune.

The official said the protesters will face legal charges and called on Serbian authorities to avert such instances in future.

According to the International Herald Tribune, the act was apparently co-ordinated with the Serbian government, which has denounced Kosovo's proclamation of independence and pledged to restore authority over northern Kosovo.