First look at brutal brawl between teens and rail employees

Footage has emerged of a vicious brawl between teenagers and railway guards at Adelaide Railway Station.

At 7pm on a Sunday night, a scuffle broke out at the entrance to the station.

A teenager was struck in the head and another tackled to the ground, before a railway worker lands another blow.

The confrontation happened on April 13 but this vision is being seen for the first time.

“They seemed a little bit aggressive,” one witness said.

The Transport Department refused to say what provoked the incident, issuing a short statement saying Adelaide Metro employees had the power to detain anyone committing a "serious offence".

There is a police station nearby on Hindley Street, but officers didn't arrive for some time

They are now investigating the entire incident including "allegations that offences occurred”.

Transport officials wouldn't say what action - if any - has been taken against the employees.

In December 2011, the department sacked Jamie Dransfield over an attack at Mawson Lakes interchange despite the rail worker claiming he was provoked by two drunk and abusive passengers.