A second person has died at the same block of flats in Lostock Hall in the space of a five days.
South Ribble Police were called to the building in Watkin Lane during Monday (8 April).
A 41-year-old woman was found dead at the scene.
A spokeswoman for the police said: “Her death is currently being treated as unexplained but at this stage is not believed to be suspicious and enquiries are ongoing.”
Police cordoned off the address shortly before 6pm on Monday.
It follows the death of a 35-year-old man on Thursday (4 April). His death was also not treated as suspicious.
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