Detectives have named a missing 19-year-old woman - who police fear has been murdered - as Amelia Arnold.
Police and scene-of-crime specialists are examining a property in Hadrian's Walk in Stevenage.
Witnesses who may have seen suspicious activity at the address between Wednesday and Friday are also being asked to come forward.
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Patchy rain affects northern areas of the UK in the next 24 hours. Elsewhere, dry but rather cloudy.
Marjorie and Micheal Cawdery, both 83, were found dead in their house in Portadown, Northern Ireland on Friday.
Ann Myatt, who is contesting Jo Cox's former seat, told a hustings: "We've not yet shot anybody so that's wonderful."