NATO on September 29 said it would beef up its KFOR peacekeeping Kosovo force amid rising tensions in the predominantly ethnic-Serb north. "Yesterday the North Atlantic Council authorized additional forces to address the current situation," the alliance said in a statement on September 29. It did not say how many more troops it would send to Kosovo. Four people were killed on September 24 in an attack at a 14th-century Orthodox monastery in north Kosovo when some 30 gunmen stormed the monastery, sparking a gunbattle with Kosovar police. In May, violence erupted when Kosovar authorities tried to install mayors in some Serb-majority towns. Dozens of KFOR peacekeepers and some ethnic Serb protesters were injured.