Detectives investigating a knife-point robbery have released CCTV images of two people believed to have boarded a train at East Croydon station.

On November 18 at around 11pm, the victim, a 17-year-old young boy, was travelling on a train from Gatwick Airport to Preston Park.

He was approached by two men who tried to engage him in conversation for a short time.

"One of the men was noticeably intoxicated," a British Transport Police spokesman said.

"They became increasingly more threatening and reached into the victim's jeans as the train was approaching Burgess Hill, trying to take his wallet.

"The victim put his hand on his pocket to try and stop them, and one of the men pulled up his top and told him he had a knife."

The teenager then handed over his wallet, and the man then took out the knife and told him to hand over his phone too.

"The victim was threatened further as he left the train.

It's believe the two men boarded the train at East Croydon and left at Preston Park.

Detectives believe the men in the CCTV images may have information which could help their investigation.

If you recognise them or have any information please contact BTP by texting 61016 or calling 0800 40 50 40 quoting reference 567 of 18/11/19.

Alternatively you can call Crimestoppers anonymously on 0800 555 111.