A Serbian court has ordered a senior Kosovo police official to be detained for 30 days to prevent him from fleeing after being arrested on suspicion of terrorism.

The arrest of Nehat Thaci, the head of Kosovo police for the northern town of Mitrovica, and Saturday's ruling by the court in the southern city of Nis are signs of continuing tensions in the volatile Balkans.

Thaci was detained while crossing from Kosovo into Serbia Wednesday evening. Kosovo authorities 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, but has joined EU-backed talks on normalizing ties to advance membership efforts.

No details about the allegations against Thaci have been disclosed.