An armed gang is on the run after breaking into a bank wielding sledgehammers and demanding cash.

The attempted robbery happened at about 5pm on Friday at the HSBC branch in Ditchling Road, Brighton.

According to witnesses, three masked men armed with sledgehammers forced their way into the bank and told cashiers to hand over money.

One member of staff was punched and kicked during the raid.

But the gang fled the bank empty handed before police arrived, making off in a “dark-coloured” car, possibly a BMW.

Police confirmed no arrests had yet been made and officers are believed to be studying CCTV footage of the attack for clues.

One witness to the aftermath of the raid said: “It was just a normal afternoon but we suddenly saw police rushing to the bank. No one knew what was going on.

“I don't think anyone around really saw what happened because it all went on inside the building.

“The police stayed around for hours questioning people. It's just such a shock because you don't expect something like this to happen here.”

Shop owners in the area said they had been oblivious to the raid even as it unfolded just yards away.

One said: “It must have been over pretty quickly because we didn't notice anything until the police arrived.

“I've never known anything like this to happen here. It's pretty scary, to be honest.”

A spokesman for the police said that up to five people could have been involved in the raid.

Any witnesses to the raid should call Sussex Police on the non-emergency number 101.