Robbers knocked a security guard to the ground but dropped the cash box they had stolen as they ran away.

The victim was struck from behind as he carried the cash box towards the Abbey branch, in Pitsea Broadway, at 8.40pm on Friday.

The robbers dropped the cash box as they ran off towards McDonald's where they leapt into a getaway car.

The first robber is described as black, aged between 22 and 25 and plump with chubby cheeks.

He was about 5ft 10ins tall and was wearing a woolly, peaked, army style hat, a grey hooded top, baggy, grey sweat pants and dark trainers.

He was well spoken with an English accent.

The second robber was also black and aged between 18 and 22.

He was about 6ft 2ins tall and of medium build.

He was wearing a dark hooded top, a dark Parka style jacket and blue jeans.

Anyone with information about the robbery is asked to call Billericay CID on 01277 631212.