Indonesian police have arrested at least 15 Muslims suspected of participating in violence against Christians on Sulawesi island in recent years, official said Tuesday. The men, identified during eight months of police surveillance, are suspected in 13 cases dating back to 2001, including shootings, beheadings, bombings and robberies, said national police spokesman Brig. Gen. Anton Bachrul Alam. Investigators are hunting another 29 suspects still at large, he said.