An off-duty police officer was stabbed to death in what appears to be a robbery in Kleinvlei, Cape Town on Sunday.

Western Cape police spokesperson Lieutenant Colonel Andrè Traut confirmed that the officer was murdered in the early hours of the morning.

"The 28-year-old constable stationed at Delft police station was leaving a shop in the area, accompanied by a friend, when he was stabbed to death during an apparent robbery by two unknown suspects who are yet to be arrested," Traut said.

A murder case is under investigation.

The incident comes after two law enforcement officers were shot dead while protecting workers at a construction project in Philippi on Wednesday.

Officer Jan Nieuwenhuys, 49, had 25 years of service and was due to retire at the end of the year. He was a father of four. Simtembile Nyangiwe, 43, was a father of three children and the youngest was only 11 months old.