Condemning the recent attack on a church in Chhattisgarh, Meghalaya Chief Minister Conrad K Sangma on Friday said acts of vandalism on churches are "unfortunate" and must stop at once. A church was vandalised and six police personnel, including an IPS officer, were attacked and injured on January 2 during a protest by tribals in connection with an alleged religious conversion in Chhattisgarh's Narayanpur city, police had said.