Four masked Palestinian gunmen carjacked a UN-marked vehicle in Gaza City on Thursday, in the latest act of violence against UN workers in the coastal strip, a spokesman for the UN's refugee mission in Gaza said. The gunmen blocked a vehicle marked with the emblem of the UN Relief and Works Agency with their own car, and forced out the driver, who was traveling alone, said Adnan Abu Hasna, a spokesman for the agency in the Gaza Strip. The driver, an unidentified Palestinian staff worker, was unharmed. Although carjackings are prevalent in Gaza, they almost always involve locals. But parked UN cars have been stolen, and just last week, gunmen opened fire on a vehicle carrying the UNRWA chief in Gaza, John Ging. Bullets were fired at the vehicle, but no one was hurt in the kidnap attempt. UNRWA has about 11,000 staffers operating in Gaza.