A post office in Hove has been held up in an armed robbery for the third time in three months.
A man threatened staff and customers with a firearm shortly before 9.30am today and demanded money.
Sussex Police said that staff handed over money and the robber fled in a getaway car.
He abandoned the vehicle in Brighton and escaped on foot with police giving chase but losing the man.
Two women who were in the shop at the time were treated for shock by the ambulance service, but there were no other injuries.
Detective Inspector Lee Horner, from Brighton CID, said: “It was very busy on the streets when the man left the post office and we would like to hear from anyone who thinks they may have seen him making his escape.
“We are particularly keen to hear from anyone who saw him after he abandoned the car in Norfolk Road, Brighton.”
The man is described as dark skinned, possibly North African, 5ft 9in tall, of medium build and clean shaven. He was wearing a dark-coloured beanie style hat and a dark-coloured jacket and jeans.
Anyone with information is asked to contact Sussex Police on 0845 6070999.