An 86-year-old man has been arrested on suspicion of murder after female human remains were found in a septic tank.
The bones were discovered in Kempsey, Worcestershire, on 12 July during a routine emptying of the tank, police said.
Officers said the deceased was “likely to be” local woman Brenda Venables, who went missing in 1982.
The arrested man, from Kempsey, was in custody helping officers with their inquiries, West Mercia Police said.
Mrs Venables, 48, was reported missing by her farmer husband David from the couple’s then home in Bestmans Lane, Kempsey.
On Tuesday police officers were carrying out searches at the bungalow where Mr Venables, 86, now lives in the village.
A force spokesman said detectives were still awaiting DNA results but “the general circumstances lead us to believe” that the remains are likely to be those of Mrs Venables.
The remains were discovered after the tank was drained during routine maintenance.
Earlier this month police said they were confirmed as female in a post-mortem report.
They hoped DNA tests would reveal the identity, but warned it could be a “lengthy process”.
The discovery was made eight miles from Pershore where police were searching for missing estate agent Suzy Lamplugh.
That search ended on 17 July and police confirmed the Kempsey discovery was not linked to Ms Lamplugh, who disappeared from London in 1986.
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