AN armed bank robber tried to steal cash while terrified cashiers looked on in horror just three weeks after an almost identical incident took place on the same premises.

But the man fled empty-handed after smashing the security screen in front of the cashiers at the HSBC bank, in Gerrards Cross, on Thursday at 3.15pm.

He made off down Ethorpe Close and was last seen turning into Orchehill Avenue.

The bank, in Packhorse Road, was previously targeted on February 23, when a man with a plastic carrier bag demanded money from a cashier.

In exactly the same way as the latest incident, the robber tried to smash the cashier's screen before making off down Ethorpe Close.

On that occasion time, however, he escaped with an undisclosed amount of cash.

Police have not ruled out the possibility the two incidents are connected.

In the latest incident, the man was described as white, around 35 to 40 years old, 6ft tall and of heavy build. He was wearing a black balaclava, a dirty blue jacket with a hood, dark trousers and dark shoes.

The man who carried out the first robbery was wearing a distinctive hooded sports jacket, blue with two bright yellow horizontal stripes at the bottom and along the arms, blue jeans and brown shoes.

Witnesses should call Amersham CID on (01494) 465888 or Crimestoppers on 0800 555111