The public prosecution department has launched a criminal investigation into an incident in which a police officer shot at a car he thought was driven by armed robbery suspects.

The department said in a statement on Thursday that the officer involved may not have acted in line with police guidelines for firearms use.

The incident took place on the night of January 12 following a break-in at a house in Hempens, just south of the Frisian capital.

Witnesses told the police that two people had fled the scene in a car. A short while later, a “suspicious” car with two people in it was spotted in the locality. The car drove off when approached by police officers, one of whom drew his gun and fired it.

Later on the car left the road and the two occupants, Leeuwarden men in their 30s, were both seriously injured and taken to hospital. It later transpired they had nothing to do with the robbery.

The police officer who fired the gun is considered a suspect and will be questioned as one, the department said.

An official report in May said the police drew their guns 1,888 times last year and fired them in warning 92 times and directly 162 times.