A learner driver has been charged with killing a pedestrian after a car ploughed into a group outside a popular Melbourne comic convention.

A 20-year-old man died and another man the same age was seriously injured when a Toyota sedan mounted the kerb outside Melbourne Showgrounds in Ascot Vale just before 5pm on Saturday.

An off-duty officer and bystander intervened and arrested the driver after the car struck the duo and continued along the footpath, police said.

The incident happened outside the Supanova Comic Con & Gaming Event, a two-day fan convention hosted at the showgrounds.

On Sunday, a 33-year-old Werribee man was charged with dangerous driving causing death and culpable driving.

He was unlicensed with only a learner permit, police said. Further charges are expected.

The accused driver was due to appear before Melbourne Magistrates Court on Sunday afternoon.

Victorian Premier Jacinta Allan described the crash as a “tragic incident that should never have happened”.

“My heart goes out to the family and loved ones of the individual who has been tragically killed … it would have been an incredibly distressing incident,” she said.

A third young man was with the struck duo but managed to avoid the oncoming car and escaped without injury.

There was a minute’s silence at the fan convention on Sunday as organisers offered their condolences in response to the tragedy.

“We here at Supanova Comic Con & Gaming are deeply saddened and distressed by the incident that occurred outside the Melbourne Showgrounds,” they said.

“Our thoughts and prayers go out to all those affected by the unspeakable tragedy that has happened on our doorstep”.

The minute’s silence was initially planned for 10am, before doors opened, but was later pushed back to midday.

Thousands of comic and gaming fans flock to Supanova every year, with the Melbourne event adding crowds of visitors to an already-busy area.

World-famous celebrities including Stranger Things cast member Jamie Campbell Bower and Andy Serkis, who played Gollum in Peter Jackson’s Lord of the Rings movie trilogy, were set to headline the expo.

-AAP