Police were called to a property at Outgate, Ambleside last night at 10:00 pm, after receiving reports that a woman had been assaulted in the property.
An investigation was launched and a man aged 48 from the Ambleside area was arrested nearby on suspicion of murder and remains in police custody.
Police are working to formally identify the woman.
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The victim initially thought strangers Kabir Hussain and Marco Martins were trying to help her as she left a pub in the early hours.