Police have released these photos of a hammer which they believe is the weapon used to kill Valerie Graves in Bosham.
It was found in Bosham by the search team working on the murder inquiry.
Miss Graves was discovered dead in a ground-floor bedroom on the morning of Monday 30 December at the house in Smugglers Lane she was looking after with three other members of her family, while the owners were away.
She died from significant head and facial injuries.
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Tuesday morning's weather for the west of the region
Tuesday morning's weather for the east of the region
The family of a Sussex teenager who died after just one punch during a night out has reached a milestone in their lifesaving campaign.