POLICE are investigating shocking footage that shows an autistic boy being beaten with spanners by a gang of youths outside a Melbourne school.

The footage, obtained by the Herald Sun , shows Quinn Lahiff-Jenkins being attacked by five other teens.

The harrowing video shows the 14-year-old being pulled off his bike as the youths surround him outside Northcote High School, north of the CBD.

SEE THE FULL VIDEO ON THE HERALD SUN

One youth pins him to the ground while others punch and kick his body.

The teens, who attack him with spanners, shout "have you got a problem?" as he tries to defend himself against the blows.

A spokesman for Victoria Police confirmed it was investigating the assault, which occurred on St Georges Rd, Northcote, about 3.45pm yesterday.

"Investigators have been told a boy was assaulted by a group of teenagers," the spokesman said.

Police also confirmed the teenager suffered bruising to his face and legs, and was taken to hospital.

He could not comment further due to the ongoing investigation.

However Quinn's mother Carmen Lahiff-Jenkins said her son, who was back in mainstream school this year, was now too scared to go outside.

"There are marks on his body but mental health is the biggest issue," she said.

She told the Herald SunQuinn rode his bike to school to confront bullies who had targeted him and another friend who was also on the autism spectrum.

Quinn told his mother the group had called him homophobic names and wanted to protect his friend.