Three teenagers were threatened with a knife during a robbery in Rastrick on Tuesday night.
The group, who were aged between 16 and 17, were walking near Carr Green park at around 7.30pm, when they were approached by two other teens who brandished a flick knife and demanded they hand over cash.
The gang also told one of the victims to hand over their black North Face jacket, and gloves and a black New York Yankees baseball cap. The suspects then fled on foot.
Det Sgt Nick Speed, of Calderdale CID, said: “This was an extremely frightening incident for those involved and our enquiries remain ongoing.
“I would appeal for anyone who witnessed the incident or anyone who has any information to get in touch with police.
“I would also urge anyone who saw two males acting suspiciously in the area or anyone has come across the items taken by the suspects, to also get in contact.”
Both suspects are around 16-18. One is described as mixed race, 5ft 8in tall, of skinny build, with a short moustache. He was wearing black jogging bottoms, a dark coloured puffa jacket and dark coloured trainers.
The second suspect is described as white, with a dark complexion and is 6ft tall. Information can be passed to Calderdale CID on 101, quoting crime reference 13170165077.