A man waited for more than an hour for police to arrive after he was attacked.

Dave Miller managed to dial 999 after being punched repeatedly around the head by his assailant, who remains at large. But he had to wait 73 minutes before officers responded to his call.

Sussex Police today expressed regret over the incident and have launched an investigation.

The case has been taken up by a Adur district councillor Julie Searle and both she and Mr Miller have complained there are not enough police.

Mr Miller, the 61-year-old managing director of Boustead International Heaters (BIH), of Southwick Square, was called to his offices on Saturday after an alarm bell was triggered.

He dashed into the building to ensure it was secure and, a few minutes later, after determining it was a false alarm, he re-parked his car.

He was then walking to a porch outside his building when he was threatened and attacked.

Mr Miller, who is married and employs his sons at his company, was punched about the head several times before being thrown onto a nearby car.

He dialled 999 at 9.45am and was treated for cuts and bruises at the scene by an ambulance crew. But he had to wait for police.

Ms Searle, the council's deputy leader and who acts as a consultant for BIH, said: "Mr Miller has a heart condition and was badly shaken. He feels strongly about lack of police numbers.

"Neither he nor I blame the police but it highlights the fact we need more officers.

The delay in this case was totally unacceptable and I have written to the police district commander and Chief Constable Ken Jones."

A spokeswoman for Shoreham police, who cover Southwick, described the delay as "unfortunate" and added: "It will be looked into and, hopefully, it will not be repeated."

The spokeswoman said Mr Miller's call was downgraded from a top priority because the assailant had left the scene.

The offender is in his late 20s, 5ft 8in, with short dark hair. He was driving a white Bedford van.

Witnesses should call Shoreham CID on 0845 6070 999.