Two people have been arrested in connection with three deaths linked to a suspected dangerous batch of drugs.
A woman and two men died in South Shields, South Tyneside, on Tuesday, Northumbria Police said.
A man in his 30s and a woman in her 20s were arrested on suspicion of being concerned in the supply of Class A drugs.
Det Insp Emma Martin said the investigation was “at a very early stage”.
She urged people to avoid speculating “online and in the community” as it could prove harmful to the police inquiry.
The force confirmed a man and woman in their 30s and a man in his 40s were found dead on Tuesday.
Their next of kin have been informed.
Police added the deaths were currently being treated as “unexplained”.
Det Insp Martin said: “We are exploring the possibility that all three deaths are linked to drugs and possibly the same batch which has led to fatal medical episodes.”
Drug users are being warned to “be mindful” as the batch of drugs linked to the investigation could have “fatal consequences”.