THE Flying Squad is appealing for witnesses after an armed robber opened fire with a handgun outside Sainsbury's, in Chislehurst.

The robber struck on March 21 at about 11am when he threatened a Securitas guard who was taking money into the High Street supermarket at the time.

According to police the gunman attacked the van at the back of the supermarket.

After demanding the guard hand over cash, the gun-toting robber fired a single shot into the air.

He then snatched the case which contained money and fled down an alleyway to a waiting car.

The getaway car is thought to have been a black Mercedes.

The police's armed response unit, and dog-handlers sped to the scene, but the two suspects had already made their escape.

Police said no-one was injured in the robbery, but the driver was “shaken”.

Neither Sainsbury's nor the police would reveal how much money had been stolen.

Securitas management were unavailable for comment.

The main suspect is described as a white male 25 years old, 5ft 9ins wearing a cream jacket, black trousers and a black balaclava.

If anyone has any information about the robbery or saw the suspect escaping in a dark or black vehicle, they should call the Bob Currie at Tower Bridge Flying Squad on 020 7232 6530.

They can also call the police anonymously on 0800 555 111.