A brazen thief died in a robbery gone wrong after tripping over and hitting his head on concrete while fleeing the scene.

He and an accomplice attempted to rob Indian Mahal, a restaurant in Baxter, Melbourne, shortly before 11:30pm on Saturday night.

The pair attacked 55-year-old father, Nar Khatri, a father-of-two who has worked in the restaurant for 15 years.

One of the men is accused of biting off the victim's thumb and escaping with $1000 in cash, before tripping on the way out and smashing his head on the concrete footpath.

The duo were attempting to steal Mr Khatri's car to make a quick getaway. The man's accomplice fled the scene - leaving his partner behind, police said.

They attacked 55-year-old father, Nar Khatri (pictured) who worked in the restaurant for 15 years

Mr Khatri has since undergone surgery on his thumb and remains in hospital recovering

A friend of Mr Khatri, Suzette Donald, told 7News she was certain the unnamed assailants were locals.

'I'm sure they were locals because they knew his movements and they had no car,' she said.

'He has head injuries, I believe from being bashed and they bit off the top of his thumb.'

He has since undergone surgery on his thumb and remains in hospital recovering.

Police say the 'exact cause of his death is yet to be established, however is not being treated as suspicious.'

The investigation is ongoing.

Anyone with information is urged to contact Crime Stoppers.