The grandmother of missing schoolgirl Tia Sharp has been arrested on suspicion of murder.
Christine Sharp, 46, was detained following the discovery of a body at her home in New Addington, near Croydon, south London, yesterday.
Her partner Stuart Hazell, 37, was arrested last night on suspicion of murder.
Ms Sharp's next-door neighbour Paul Meehan, 39, was later taken into custody on suspicion of assisting an offender.
In the wake of Mr Hazell's arrest, Scotland Yard today announced that a 46-year-old woman and 39-year-old man had also been arrested yesterday.
Sources later identified the two further suspects as Ms Sharp and Mr Meehan.
The 12-year-old girl was reported missing last Friday.
A team of forensic officers discovered the body during a fourth search of Tia's grandmother's home, prompting some to ask questions about Scotland Yard's handling of the case.
Police reportedly removed the body, which is yet to be identified, from the terraced house late last night after Mr Hazell was taken into custody.
A post-mortem examination is expected to take place in the coming days.
Police have not revealed where the body was discovered, but officers were seen taking a ladder into the property yesterday afternoon, sparking rumours that it may have been in the loft.
A dark holdall was later seen being removed from the house.
Mr Hazell was arrested in a public place - believed to be a park - in the south London borough of Merton at about 8.25pm last night.
It is understood he was identified by schoolgirl Chloe Bird, 11, shortly after he bought alcohol in an off-licence.
Her stepfather Nick Keeley, 40, said she came back home and told him that she had spotted Mr Hazell.
He said he was not then aware he was wanted by officers but when his step-daughter directed him to news reports he rang the police.
"The police were here within five minutes," he told Sky News.
"I hadn't even finished telling them where he was, and they were here.
"There were like five cars within five minutes and then the whole area was swarmed with police."
There was a significant police presence today at the house where the body was found.
Flowers, teddy bears and candles remained near the house after neighbours and friends left tributes to Tia last night.
One message read: "Rest in peace Tia. Justice will be served."
Another read: "Tia Sharp, beautiful angel, taken too soon, our thoughts are with all of you."
Neighbours continued paying their respects this morning, with one woman breaking down in tears after leaving flowers.
Nicky Taylor, 46, and Shara Kinsley, 40, lit two candles for Tia.
Ms Taylor said: "She's only a child, it's so sad."
A poem was left with a photo of Tia which described her as "heaven's little angel".
Comments have been closed for legal reasons.