Three injured after ambulance at Melbourne crash struck by truck

An ambulance has been struck by a semi-trailer in Melbourne while pulled over attending to a separate crash.

Authorities said the emergency vehicle was called after a car crashed into the guardrail on the East Link onramp in Dandenong North.

Around 5.45am, the semi-trailer collided with the ambulance and the car that had originally crashed.

The driver of the original car, the man from the truck and another man who stopped to help were all taken to hospital with minor injuries.

The paramedics were uninjured.

Drivers are being urged to avoid the area.