Police are investigating after two men entered through the rear door of the John Street newsagency about 4am.

They demanded cash from a 32-year-old male employee, police said, before the worker became involved in a struggle with the pair and forced them out of the building.

Investigators from Hunter Valley Police District established a crime scene and are looking for the would-be thieves, who did not manage to steal anything during the failed heist.

The 32-year-old was taken to Singleton Hospital for treatment of minor cuts and grazes to his arms and forehead.

Business owner Ken Lawson told the Newcastle Herald on Thursday afternoon the employee had been released from hospital.

Despite the ordeal, he said the worker had said he planned to turn up for work on Friday.

Mr Lawson said the 32-year-old was a long-time employee - he had been working at the newsagency for at least a decade.

He said it was the first attempted hold-up in the decades since he started running the business.

"Put it this way, we've been here 30 years and this is the first time this has happened," he said.

Police said in a statement on Thursday that their investigation was ongoing.

They asked anyone with information about the attempted hold-up to contact Crime Stoppers on 1800 333 000. Information can be given to police anonymously through Crime Stoppers.

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