Man in custody over Melbourne shooting

A man has been arrested following the fatal gunning down of a man at a Melbourne shopping plaza.

The victim, 24, died in hospital late on Monday after being shot multiple times in a car park at Campbellfield Plaza earlier that afternoon.

Homicide police arrested a 27-year-old man from Greenvale on Tuesday morning. He has not been charged.

The victim, from Southbank, was wounded by a man who approached him and opened fire about 3:30pm outside Officeworks.

Shoppers, reportedly including young children, fled as the gunman began shooting.

Police say the shooter took off after the attack in a red car heading towards the Dallas area.

More shots were fired a short time later near the intersection of Riggall and Blair streets in Broadmeadows.

It's believed those shots were fired into the air.

Just hours later a 51-year-old Templestowe Lower man turned up at Northern Hospital in Epping with suspected gunshot wounds.

Police have said it's too early to tell whether the two incidents are linked.

The armed crime squad is investigating how the 51-year-old received his non-life threatening arm injury.