No one was reported injured in the blast late on February 19.
It was not immediately clear what caused the explosion, but police said investigators suspected the UN mission to Kosovo may have been the target of an attack.
The incident occurred as Serbian and Kosovar Albanian representatives are preparing to meet on February 21 in Vienna to resume UN-mediated negotiations on Kosovo's future status.
The Serbian government has already rejected a proposal put forward by UN envoy Martti Ahtisaari, which calls for self-governance for Kosovo under international supervision. Ethnic-Albanian leaders want full independence for the territory.
Kosovo formally remains a Serbian province, though it has been administered by the UN since the 1999 NATO bombing campaign ended a Serbian crackdown on the ethnic-Albanian majority.
THE WORLD'S NEWEST NATION? The region of Kosovo has a population of more than 2 million, some 90 percent of whom are ethnic Albanians. It was one of the poorest regions in the former Yugoslavia, but has considerable mineral wealth and an enterprising population, many of whom work abroad but keep close contact with Kosovo. All ethnic Albanian political parties seek independence on the principles of self-determination and majority rule. They feel that Serbia lost its historically based claim to what was its autonomous province under the 1974 constitution by revoking that autonomy in the late 1980s and then conducting a crackdown in 1999 that forced some 850,000 people to flee their homes.
Since NATO's intervention that year to stop the expulsions, Kosovo has been under a UN administration (UNMIK). The UN has begun to gradually transfer functions to elected Kosovar institutions. The primary Serbian concerns are physical safety for the local Serbian minority, a secure return for the tens of thousands of Serbian displaced persons, and protection for historic Serbian religious buildings. The main problems affecting all Kosovars, however, are economic. Until Kosovo's final status is clarified and new legislation passed and enforced, it will not be able to attract the investment it needs to provide jobs for its population, which is one of the youngest and fastest growing in Europe. Prosperity is widely seen as the key to political stability and interethnic coexistence in Kosovo, as is the case in much of Southeastern Europe.
For an archive of RFE/RL's coverage of developments in the disputed region of KOSOVO, click here.