A woman was arrested on suspicion of aiding or abetting suicide following the death of a man.
On Thursday at 1:45 am BST, police were called to an address on Blackburn Road in Clayton-le-Moors due to concerns for the well-being of a man and a woman.
Police discovered that a 19-year-old man had died and a 46-year-old woman had been seriously injured, Lancashire police said.
The woman received first aid before being taken to hospital where she is in stable condition.
She has since been arrested on suspicion of helping or encouraging suicide.
The death is currently being treated as unexplained and there is no indication that other people were involved, added the force.
A post-mortem examination has been carried out but the cause of death has not yet been established, said the police spokesman.
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