A robber who has targeted three shops brandishing a knife forcing staff to hand over cash is behind a fourth attack in 24 hours.

Attacks took place between Thursday and Friday afternoons. They began with Coral in Wincheap being raided, followed by robberies at Chartham Post Office and Coral in Herne Bay.

Now police have confirmed a fourth incident is being linked to the same man.

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The most recent robbery was reported at 8.53pm yesterday at the Premier NK Mini Market in Godfrey Gardens, Chartham.

It was alleged that a man entered the shop and threatened a member of staff with a knife before he was disturbed and left empty-handed.

A post from the store read: "We just had a robbery by this man in the shop...we are safe and well."

Detectives are already investigating whether the same robber was responsible for the three earlier attacks.

The force issued a CCTV of the suspect and are appealing for information.

Police have issued this timeline of the previous three robberies:

Thursday just before 5pm: a man walks into Coral bookmakers in Wincheap, Canterbury, and used a knife to make threats against customers and staff before leaving with cash.

Friday, 10.30am, post office in Shalmsford Street, Chartham targeted with man alleging to have threatened member of staff before escaping with money from the till.

Friday 2.15pm: a man reported to have stolen cash from Coral bookmakers in Sea Street, Herne Bay, after threatening staff.

Witnesses say he is about 6ft 2ins tall, slimly built and thought to have a ginger beard.

He was said to be wearing a green/ dark grey bomber jacket and dark tracksuit bottoms.

No one was injured in any of the incidents.

Detective Chief Inspector Nick Gossett of the Kent and Essex Serious Crime Directorate is leading the investigation into the offences.

He said: "We are treating these incidents very seriously and are carrying out a number of lines of enquiry to identify the person responsible and arrest him as soon as possible.

"A common description of the man from each reported offence is that he had a ginger beard, wearing a black motorcycle helmet and a puffer jacket.

"I would urge anyone who witnessed any of these incidents or who may know who is responsible to call the appeal line."

"I would also ask shopkeepers, bookmakers and other business-owners to remain vigilant and please report anything suspicious by calling 101 or 999 in an emergency.’

Officers would like to hear from anyone who believes they may have information or recognises the man in the photograph.

Anyone with information about any of the incidents is asked to call Kent Police on 01843 222289 quoting reference ZY/22732/17.

Alternatively contact Kent Crimestoppers, anonymously, on 0800 555111.