Police have named two brothers wanted in connection with the so-called Benson & Hedges robberies.

David Whittle, 27, and Simon Anthony Whittle, 30, are from Manchester.

Detectives took the unusual step of releasing the two names following nine armed raids on shops and off-licences in two weeks.

Police have called the raiders the Benson & Hedges Gang because they have grabbed packets of the cigarettes during a number of hold-ups.

The Whittle brothers are described by police as transients and have been staying at a number of addresses in the Brighton and Hove area. Detective Inspector Peter Laverick, heading Operation Benson, said the two should not be approached and urged anyone with information to dial 999.

He said: "We are asking members of the public to call the emergency line immediately. "

Two shop assistants have been attacked and the robbers have armed themselves with knives, screwdrivers and a wheelbrace.

One assistant, Nigel Hill, refused to hand over cash and was floored with a head-butt. He was knocked unconscious and suffered a 1in cut above his nose.

Mr Hill, 42, was working at Thresher in Longridge Avenue, Saltdean, on Thursday evening when the raiders struck.

Another assistant, Matthew Wicks, dodged a head-butt when the same robbers tried to steal cash at Unwins off-licence in Sutton Park Road, Seaford, an hour later. Mr Wicks managed to push one man into the street.

One victim told how he came face-to-face with the offenders on Tuesday.

Robert Ford, 36, manager of Thresher off-licence in Western Road, Hove, said: "It was all over quickly. They marched into the shop, pulled a knife and demanded cash from the till.

"There wasn't much money in it so they forced me to open a safe. One of them asked me to hand over some packets of Benson & Hedges cigarettes but the other intervened and said 'let's go'."

Both robbers are white and one is 5ft 9in and wore an Adidas jacket. The other is 5ft 7in with receding hair.

Robberies have occurred from Hove to Seaford: April 24, 9.15pm, Co-op, High Street, Rottingdean, Brighton; April 30, 6.30pm, Thresher, Holland Road, Hove; May 1, 10pm, Thresher, Queen's Park Road, Brighton; May 2, midnight, Asda, Brighton Marina; May 4, 11pm, BP service station, Kingsway, Hove; May 6, 4.30pm, Thresher, Western Road, Hove; May 7, 9.30pm, Co-op, High Street, Rottingdean, Brighton; May 8, 8.05pm, Thresher, Longridge Avenue, Saltdean, Brighton; May 8, 8.55pm, Unwins, Sutton Park Road, Seaford.