Saskatchewan RCMP collision analysts are investigating after an RCMP officer rolled his unmarked cruiser on Highway 4 on Thursday evening. RCMP say the incident was reported around 6 p.m. on Aug. 21 at the resort village of Cochin, located about 180 kilometres northwest of Saskatoon. According to police, an officer with the Battlefords detachment was responding to a call for service in an unmarked police vehicle with emergency equipment activated when the rollover occurred. The officer, a man, sustained serious but non-life-threatening injuries and was taken to Saskatoon for treatment. Police say the investigation is ongoing and the highway has since been reopened.