?Terrifying details have emerged of the moment gatecrashers brutally bashed a security guard at a teenage party at Aspendale.

As many as 180 people were invited to the 16th birthday party at the club rooms of Glen Street Reserve on Saturday.

The power went off about 9.30pm.

A security guard went outside to investigate when he was confronted by a group of about 15 youths.

Police have told Leader Newspapers the youths have then brutally bashed the security guard, a 53-year-old from Clayton.

They threw him to the ground and kicked him in the head and body.

Windows were also smashed, with terrified partygoers cowering inside.

No arrests have been made.