Cape Town - A 37-year-old police officer was shot and wounded while on duty in Delft in the early hours of Sunday morning, Western Cape police said.During the early morning, patrol police noticed an "unidentified suspect roaming around" in the N2 Gateway housing project, Constable Noloyiso Rwexana said."Police stopped to confront the suspect, the suspect started shooting at the members."The man fired three shots, hitting the officer in the left leg and damaging his work car. A case of attempted murder and malicious damage to state property was opened.No arrests had been made yet.This week, four police officers were killed in Johannesburg and Cape Town.On Wednesday, a 36-year-old police officer was killed during a shoot-out with robbers at the Vosloorus Crossing mall.On the same day, in the Western Cape, Petrus Holz, 50, member of the Hawks, was stabbed to death when he stopped on the N2 to inspect damage to his car after he drove over debris in the road.On Thursday morning, a 35-year-old officer was shot while responding to a business robbery in Sekampane, Temba, north of Pretoria, Gauteng police spokesperson Lieutenant Colonel Lungelo Dlamini said. He died on arrival at a local hospital.On Friday, a 34-year-old police constable was shot and killed in Jeppestown, Johannesburg, when he and a colleague went to investigate a group of men sitting in a parked minibus taxi.Deputy Police Minister Maggie Sotyu said 52 police officers had been killed since January, compared to 47 for the same period last year.