Press Association via met.polic

Stuart Hazell, 37, is wanted for questioning in what is now a murder enquiry.

Updated 5:19 p.m. ET Saturday: The grandmother of missing London schoolgirl Tia Sharp is among three people arrested in her disappearance, police and British media reported Saturday.

The day after a body was found at the New Addington home of the grandmother, Christine Sharp, 46, police were questioning her on suspicion of murder, the Guardian newspaper of London reported.

A neighbor, Paul Meehan, 39, was arrested on suspicion of assisting an offender, the Guardian reported.

On Friday night, police said they arrested the grandmother’s boyfriend, Stuart Hazell, 37, on suspicion of murder.

Hazell was arrested in the borough of Merton after a member of the public called police, who earlier in the day issued asked the public’s help in finding Hazell.

Metropolitan Police on Saturday also apologized for “human error” that delayed the discovery of the body at the Sharp home during three visits to the estate before Friday.

“A continuing review and examination of our search processes will be undertaken to ensure such a failing is not repeated,” South East London Area Commander Neil Basu said in a prepared statement.

Matthew Lloyd / Getty Images

Tia Sharp, 12, has been missing in Britain since Aug. 3. A body was found Friday at her grandmother's home.

Officials are trying to determine the identity of the body and how the person died, police said.

Tia Sharp, 12, has been missing since Aug. 3.

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Matthew Lloyd / Getty Images

Christine Sharp, the grandmother of missing Tia Sharp, leaves her home accompanied by detectives on Friday in New Addington, England.

Basu on Friday said that police are trying to determine how long the body had been in place before it was found.

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The BBC reportedthat Tia Sharp visited her grandmother’s house regularly and was believed to be alone with Hazell while her grandmother was at work the night before she disappeared.

Hazell on Wednesday told police Tia Sharp had set off shopping for flip-flops on Aug. 3, but investigators later said she did not show up on surveillance video.

On Thursday, in a television interview, Hazell denied having anything to do with her disappearance.

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