Kosovo police say a Molotov cocktail has been thrown at the offices of the country's president.

A police statement Saturday says masked attackers in the early morning threw the explosive and then broke the windows of an office used by outgoing President Ahtifete Jahjaga's staff. It was the latest in a string of attacks on public buildings with Molotov cocktails or on senior officials with eggs.

Since September, the opposition has disrupted the Parliament's work and its supporters have clashed with police to protest two deals with Serbia and Montenegro that they say undermine Kosovo's sovereignty.

The opposition has not accepted last month's election of Hashim Thaci, former foreign minister and leader of a governing political party, as Kosovo's next president. It is contesting his election at the Constitutional Court.