Flying Squad detectives are appealing for witnesses and information following two cash-in-transit armed robberies in west London.

The first robbery was at a builder's yard on Hampton Road West in Hanworth at 1.05pm last Thursday (13), and the second on Circus Road, St John's Wood, at 12.05pm on Friday (14).

In both incidents the suspects who have been described as white and aged 20 to 25-year-olds, used a hammer to threaten security guards.

Officers said the two incident are being treated as linked.

At Hanworth, one suspect was armed with a hammer and approached the guard who was able to get in his security van.

The suspect fled the scene empty handed in a black Toyota Auris, believed to have had false registration plates LP60 WJM, and was driven by a second suspect.

In St John's Wood, a male armed with a hammer robbed a security guard of a cash box as he was returning to the van.

The suspect dropped his hammer to take the cash box and left the scene in a car driven by a second suspect.

They are believed to have driven to nearby Wellington Place and drove over the cash box forcing it to open and emptied the cash out, leaving the box behind.

The hammer and the cash box were recovered and have been sent for forensic testing.

It is believed the rear end of the car and the bumper were damaged.

In both cases there were no reported injuries.

The male suspect with a hammer was described as wearing grey coloured clothing and a yellow hi-vis hood.

Witnesses or anyone with information about the incident should contact DC Steve O'Connell at the Flying Squad in Putney via 101 or call Crimstoppers anonymously on 0800 555 111 or via