A 14-year-old boy ran from a train after being forced to hand over his smartphone and wallet.

The teenager told police how the man sat next to him on a train between Bickley and Swanley and began verbally abusing him before demanding his phone and wallet.

The victim, who also believed the robber had a knife in his pocket, ran from the train at Swanley station at about 12.55pm on Saturday, March 8.

Now police have issued CCTV following the incident onboard the 12.20pm London Blackfriars to Sevenoaks service.

Officers have been pursuing several lines of enquiry, including analysing CCTV footage from on the train and at several stations.

Detective Constable Ostin Elkins, of British Transport Police’s robbery squad, said: “This was a very distressing incident for the young boy who was travelling on his own. Everyone has the right to use the rail network without the fear of crime and we are doing everything we can to catch the person responsible.

“I urgently want to speak to the man pictured as I think he could greatly help the investigation. If you recognise him, or have any other information, please get in touch.”

Anyone with information is asked to contact British Transport Police on 0800 40 50 40, or text 61016, quoting background B3 of 28/04/2014. Information can also be passed to Crimestoppers on 0800 555 111.