Two robbers stole a bike worth about £2,500 from a 13-year-old boy in Burgess Hill last weekend.
The incident occurred outside St John the Evangelist Church, in Civic Way, around 3pm on Sunday 10 November.
The victim was approached by two unknown boys aged about 15, one of whom threatened violence if he did not hand over his bike. They then made off in the direction of Norman Road.
Anyone who saw what happened or captured any relevant dash cam, mobile or CCTV footage, is asked to report it online or call 101, quoting serial 588 of 10/11.
The bike stolen was a red Trek Top Fuel 8, valued at approximately £2,500.