A man has been arrested on suspicion of supplying drugs after an 18-year-old Teesside man died in hospital.
The teenager, from Lingdale, near Redcar, was admitted to Middlesbrough's James Cook University Hospital on 15 December, but died early on Friday.
A post-mortem examination is to be carried out on Monday in an effort to determine an exact cause of death.
A 48-year-old local man was arrested on suspicion of supplying Class A drugs in connection with the incident.
Cleveland Police said properties in Scarth Close and Pease Close in Lingdale had been searched in connection with the man's death.