A woman has been arrested on suspicion of assisting or encouraging suicide following the death of a man.
Police were called to an address in Blackburn Road in Clayton-le-Moors at 01:45 BST on Thursday due to concerns for the welfare of a man and a woman.
Inside officers found a 19-year-old man had died and a woman, 46, had serious injuries, Lancashire Police said.
The woman was given first aid before being taken to hospital where she is in a stable condition.
She has since been arrested on suspicion of assisting or encouraging suicide.
The death is currently being treated as unexplained and there was nothing to suggest any other people were involved, the force added.
A post-mortem examination has been carried out but the cause of death has yet to be established, the police spokesperson said.
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