YANGON, Burma (BP) -- Ethnic Wa rebels this month shut down churches or destroyed their buildings and temporarily detained several clergymen in eastern Burma (Myanmar), sources said. On the border with China, soldiers of Myanmar's largest ethnic rebel group, the United Wa State Army (UWSA), attacked the churches in the rebel's autonomous region in Shan state, according to Christian leaders. "We confirmed that at least 12 churches have been destroyed or closed as of Sept. 20," a Christian leader who has lived in the Wa region for several decades told Morning Star News. The Wa people worship ancestral spirits, and the move by the UWSA was meant to hamper Christian missionary activity, said the leader on condition of anonymity. Most of the targets were Baptist churches in Panghsang, where Wa soldiers destroyed crosses, the source said. The headquarters of the UWSA is located in Panhsang, on Burma's border with China.