A “particularly dangerous” batch of heroin has left a man dead and 13 others being treated for overdoses in the space of 24 hours, police said.
Cleveland Police has warned drug users in Stockton some street dealers are selling the potentially lethal grade of the Class A drug.
The dead man was 50 and from the town, a force spokesman said.
He added: “Police and North East Ambulance Service are reiterating the message once again that lives are being put at risk by accepting this particularly dangerous grade of heroin.
“This bad batch of drugs was centred around the Oxbridge area of Stockton. However, there was also one victim brought into hospital from Middlesbrough.
“We have been warning drug users over the past months to be cautious as there has been a surge in these low grade drugs becoming available and they should seek the support of their service providers before putting their lives in danger.
“In particular, those who purchase their drugs via street suppliers should be extremely cautious.”