THE Aussie hip hop group that was on stage when a man performed a sickening sexual assault on a woman in the crowd has launched a stinging attack of the perpetrator.

Victorian police are on the hunt for a man who ejaculated onto the back of a woman in the mosh pit while Thundamentals were performing at the St Kilda Festival on February 8.

The band said they were “shocked and disgusted” to learn about what happened during their gig.

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“In light of those events, we would like to think that any true fan of Thundamentals that has understood the message in our music and followed our journey as a band would never commit such a disgusting and predatory act against another human being,” they said in a Facebook post, which has been liked more than 2000 times.

“Furthermore, if any of our fans were to witness something like this happening (we hope) that they would at least notify someone who could help assist the victim.

“Everyone should have the right to feel safe, no matter what.

“We 100 per cent support the young lady who suffered and hope that she is OK.”

The victim spoke out yesterday in the hope one of the crowd members who saw the incident would come forward.

“I feel violated but I’m lucky it wasn’t worse,” she said.

Senior Detective Carin Wood said “surely someone has seen something or knows who this person is”.

The suspect is described as being of Indian appearance and aged between 18 and 30, with a dark brown complexion, average build, short black hair and brown eyes with acne scars on his cheeks. He was wearing a black, long-sleeve shirt at the time.

Thundamentals have encouraged people with information about the assault to phone 1800 333 000 or submit a confidential report to Crime Stoppers.