A man has been bashed in the head with a screwdriver and had a knife held to his throat in a terrifying carjacking in Melbourne's north.

Four men set upon the 35-year-old victim as he was getting out of his car at a shopping strip on May Road in Lalor in the early hours of Thursday morning.

The group demanded his keys and mobile phone before punching and kicking him to the ground, striking his head with a screwdriver and taking off in his car.

The attack comes as the latest crime data reveals another spike in robberies including carjackings.

There were 20 carjackings and 25 attempted carjackings in the state, between December 7 and March 31, according to the Crime Statistics Agency.