A 14-year-old boy has had his phone stolen in a Stevenage park by a teenager wielding a knife – and police are now appealing for witnesses.

The incident occurred at about 6pm on Thursday in St Nicholas Park.

The boy was approached by an older teenager on a black mountain bike who asked to look at his mobile phone.

When he refused, the older boy revealed what appeared to be the handle of a knife tucked into his shorts.

The 14-year-old handed over his phone, at which point the offender rode off towards the car park entrance.

The older boy is described as black, thin and about 16 or 17 years old, with black, short, curly hair. He was topless and wearing black shorts, and was with a group of other teenagers in the park.

Det Sgt Phoebe Butfoy said: “Thankfully the victim was not injured but I understand this incident may cause concern among members of the community.

“I would like to reassure people that we are doing all we can to trace the person responsible.

“I would urge anyone who may have witnessed the incident, or who thinks they may have seen the suspect in the area around the time stated, to please get in touch.”

Anyone with information should contact the Stevenage local crime unit via 101, quoting crime reference E1/16/5765.

Alternatively contact Crimestoppers anonymously on 0800 555 111 or at crimestoppers-uk.org.