A group of youths were robbed at knifepoint by a Justin Bieber ‘look-a-like’ and his accomplices.

The four victims were sitting on a bench close to a stream in Scrase Valley Nature Reserve, between Backwoods Lane and Wilmington Way in Haywards Heath, when they were approached by three young men at about 9pm on Sunday, August 18.

One of the trio pulled out a knife and ordered the victims to hand over their mobile phones.

The first thief is described as white, about 17, 6ft and skinny, with a London accent. He was wearing a black and grey hooded top, jeans and a snap back flat peaked baseball cap.

The second thief is described as white, 5ft 10in and skinny with ‘Justin Bieber-style brown hair’. He was wearing a hoodie with the hood up.

The third thief is also white, 5ft 8in skinny and about 15. He was wearing a black hoodie and dark coloured trousers.

Police are keen to speak to anyone who recognises the description of the thieves or who saw what happened.

Anyone with information should call 101 quoting serial 8 of 19 August or Crimestoppers on 0800 555111.