Updated

Serbian police have arrested a senior Kosovo police official on suspicion of terrorism in a sign of ongoing tensions in the volatile Balkans.

Police said in a statement on Thursday they arrested a man from Kosovo, identified only by his initials N.T., "for the criminal act of terrorism." Police say he was detained while crossing from Kosovo into Serbia Wednesday evening.

In Kosovo, police spokesman Daut Hoxha told The Associated Press that Serbian police had detained Nehat Thaci, the head of Kosovo police for the northern town of Mitrovica.

Hoxha says Thaci was traveling privately when detained, and Kosovo police have demanded an explanation.

Kosovo, a predominantly ethnic-Albanian former Serbian province, declared independence in 2008 following a 1998-99 war. Belgrade has refused to recognize the split.