A gunman executed a customer in a barber's shop just minutes after greeting him in the street, a court heard.

Rafik Alleyne, 21, of Zion Gardens, Brighton, is said to have shot Andrew Sams, known as Axe, once in the head.

But jurors at the Old Bailey heard that just moments earlier he "knocked knuckles" with his 25-year-old victim - a West Indian sign of respect.

Mr Sams collapsed on the floor of the hair salon after the shooting on April 15, 2003, and died less than an hour later.

Alleyne, who denies murder, is said to have made a minicab driver take him on a "devious" route away from the scene but was later identified by several witnesses.

Michael Worsley QC, prosecuting, said Mr Sams was seen talking to Alleyne and another man outside a Jamaican food shop near the Upper Cuts barber shop in Norwood High Street, south London.

He said: "When they were joined by Andrew they were knocking knuckles with him. It is a West Indian form of respect. There was a sign of respect shortly before a deliberate execution. Andrew went into the barber shop. He was a regular customer there. He started to talk to the barber.

"The barber heard a bang behind him. He turned and saw a man he'd seen outside, running out of the door. He soon realised Andrew had been shot.

"Another witness who was sitting in the barber shop saw Andrew come in. A few seconds later he saw a man he later identified as the defendant come into the shop and fire a gun towards the back of the shop."

Mr Sams collapsed to the floor and an ambulance was called.

Mr Worsley said: "The unfortunate Andrew was still alive but within half an hour he died. Attempts were made to save him but unfortunately they were not successful."

A post mortem later revealed Mr Sams died from a single gunshot wound to the head.

Mr Worsley said that while Mr Sams lay dying, Alleyne ran to a minicab office in nearby Knights Hill.

He told the court: "A young black lad, clearly the defendant, entered in a highly agitated state. He was directed to one of the firm's taxis and asked to be driven to Stockwell.

"The taxi was driven on a very devious route, as asked for by the defendant."

The trial continues.