Three nearly simultaneous blasts rocked downtown Pristina in Kosovo late Saturday, one of them targeting the United Nations mission headquarters, officials said. No injuries were reported. The two other blasts went off near a Kosovo government building and a building housing the offices of the Organization for Security and Cooperation in Europe, or OSCE. All the buildings are within about 500 yards of one another in downtown Pristina, the administrative capital of the Kosovo region of Serbia-Montenegro. The blasts went off shortly after 9:30 p.m. (3:30 p.m. ET), U.N. spokesman Remi Dourlot said. At least three U.N. vehicles caught fire at the U.N. compound, but the main building was not damaged. No one was inside the vehicles, Dourlot said. "We have no injuries reported for the time being," he told CNN by phone. It was not immediately clear what caused the explosions. An investigation was launched and the area was sealed off.