Gardai in Cork have carried out a number of raids on the homes of suspected drug dealers, in an attempt to rid Cork City of a batch of unusually pure heroin.

Drug squad detectives seized a small quantity of substances which are to be sent for analysis but no arrests have been made.

The HSE last night issued a warning to heroin users in Cork, after two men died from suspected heroin overdoses.

Seven others have been treated for suspected overdoses- two of whom remain in a critical condition.