Pair arrested, two on the run after Victorian police officer pinned between car and van

Two men have been arrested and police are searching for two more after a Melbourne constable was pinned between a car and his van.

The incident occurred this afternoon after police stopped a vehicle on the South Gippsland Highway in the city's southeast.

But what began as a routine inspection ended with the police constable pinned between the car and police van, with the exact series of events still being investigated.

One man was arrested immediately, while another was taken into custody a short time later.

Police are still looking for two other men who fled the scene.

The constable is being treated in hospital for non-life threatening injuries.