A man's body has been found behind a disused pub in St Helens.
The man, who has not been identified but is thought to be in his 30s or 40s, was found behind the Traveller's Rest pub on Friday night.
Police are keen to trace a group of youths who stopped a man in Crab Street at about 1840 BST to say they had seen the body.
It is not known whether a weapon was used in the killing but a post-mortem test was taking place on Saturday.
Anyone with information is urged to contact police or Crimestoppers.