One man is dead and another fighting for life after a barrage of shots left four people wounded outside a nightclub in the inner-city Melbourne suburb of Prahran early on Sunday morning.

The attack occurred outside the Love Machine nightclub, near the corner of Little Chapel Street and Malvern Road in Prahran, about 3:20am.

Four people where taken to hospital, including two men, one aged 28 and another 37, whose conditions were listed as critical.

The unnamed victim killed in what police described as a drive-by shooting was the 37-year-old, a security guard from Narre Warren who worked as a bouncer at the club.

The other critically injured victim is also said to work at the club.

Two men, aged 50 and 29, have non-life-threatening injuries.

VicPol forensic specialists collect evidence from the shooting scene. Photo: AAP/Ellen Smith

“I thought it was three gunshots and then there was a bit of screaming and commotion downstairs,” a witness identified only as “Daniel” told 3AW.

“I just stuck my head out the window, which looks over Love Machine, and then everyone was running around,” he said, adding that police armed with assault rifles were on the scene in minutes.”

Detective Inspector Andrew Stamper, of the Homicide Squad, told the ABC the shots were fired at close range.

“They’re gunshot wounds from fairly close proximity, so horrific injuries,” he said.

The police investigation is focusing on the occupant of a black Porsche SUV seen speeding from the scene seconds after the fatal shots.

The vehicle was later found burnt out in an outer-suburban northern suburb of Wallert.

Police are trying to construct a coherent narrative of the wee hours’ eruption of violence, but their efforts are being hampered by conflicting  accounts.

Witnesses reported, for example, that one man ran from the scene, leaving a trail of blood that was still evident in the cold light of Sunday morning.

However Detective Inspector Andrew Stamper was unwilling to say what part the unknown fugitive might have played in the tragedy.

“We just don’t know if that’s one of the four people that we’ve caught up with, or potentially whether there was somebody else who was injured,” he said.

A crime scene has been established and police are urging people to avoid the area, which remained closed to passing traffic throughout Sunday morning.

“An investigation is underway and the exact circumstances are still being established,” a police spokesman said in a statement.

Anyone with information is asked to contact Crime Stoppers on 1800 333 000.

-with wires