A batch of killer heroin could be circulating on Huddersfield's streets.
Now police have warned users to use extreme caution following two suspected drugs-related deaths in different parts of West Yorkshire on Saturday.
Police say they fear batches of unusually strong heroin may be in circulation in the region.
Enquiries are continuing into the deaths of a 36-year-old man in Leeds and a 27-year-old man in Normanton, near Wakefield. Officers were called to Compton View in the Harehills area of Leeds at 8.22am and found the body of a 36-year-old at the property.
Paramedics were called later that day to Park Green, Normanton, following reports of a 27-year-old man suffering breathing difficulties. He died at the scene.
Both deaths are being treated as non-suspicious and, while toxicology results are being awaited, it is believed they are drugs-related. The deaths are not currently being linked by detectives.
Det Chief Insp Jim Dunkerley of West Yorkshire Police, said: “Enquiries remain ongoing into both these men’s deaths. While we are awaiting full toxicology results we do believe these deaths are Class A drugs related.
“The force is aware of warnings issued by other forces in the Yorkshire and Humber region about unusually strong heroin or heroin derivatives potentially being in circulation and it seems prudent to issue a warning to local drugs users.
“Taking Class A drugs is, of course, extremely risky in itself but we would urge users who experience unusual side effects from taking heroin or substitutes to seek medical help via 111 or in life threatening situations 999.”