Senior officers attempted to head off criticism of their inquiry into the 12 year old's disappearance – which has now become a murder investigation – after the discovery of the body during the fourth search of the terraced house in New Addington, south east London.
Stuart Hazell, 37, who lived at the property with Tia's grandmother Christine Sharp, was arrested in Merton, south-west London. He is being held on suspicion of murder. Hazell was arrested at 8.25pm when a member of the public called police.
As Hazell was being arrested, a senior Metropolitan police officer acknowledged there would be many questions asked about why they had taken so long to find the body.
No identification has taken place yet but there is little doubt that it is that of the missing schoolgirl, who was on summer holiday from Raynes Park high school, and went missing more than a week ago, on Friday 3 August.
"A number of searches took place at the address," said Commander Neil Basu. "When Tia was first reported missing, officers searched her bedroom as is normal practice … A further search of the house took place in the early hours of Sunday morning by a specialist team. This was followed by another search of the house by specialist dogs on Wednesday lunchtime."
But it was only on Friday afternoon, after a full forensic search of the house was carried out that the body was found.
It is understood it was found in the confines of the house, not outside or in any outbuilding.
Tia's mother Natalie was informed of the discovery on Friday afternoon.
Hazell was believed to be the last person to see Tia alive. He said she had left the house at noon to go into Croydon to buy some flip-flops but there was always a suspicion that the schoolgirl had not gone far from the property.
Police were also following up two sightings of Tia which suggested that she might have left the house.
As the inquiry went on, however, Hazell's claim that Tia had gone into Croydon was not backed up by CCTV footage.
Examining hundreds of hours of tape, police failed to find any trace of Tia in the town, and their focus returned more intently to the house in New Addington.
By Friday, a decision was made to search again, in a detailed and extensive way and Ms Sharp was asked to leave the property. When asked where Hazell was, Christine Sharp said: "I don't know where Stuart is; he is out doing his own thing. He has had it hard, he knows the finger is being pointed at him."
Police interviewed Hazell as a witness on Wednesday but released him without further action. He was never arrested.
In an interview with ITV News on Thursday, Hazell denied any involvement in the disappearance of Tia.
"Did I do anything to Tia? No, I didn't. I love her to bits. She is like my own daughter," he said. "I know deep down she walked out of here. I know deep down she walked down that path. What happened after that I don't know."
It was Hazell who led a candlelit vigil this week, wearing a white T-shirt with a picture of the missing girl and the words: "Find Tia" beneath it.
Basu said the family had been kept up to date with developments: "Our priority is to support the family of Tia at this distressing time and identify the body."
Friends on the estate have been walking the streets all week, carrying posters of Tia and asking the public for help in finding her. Within minutes of the discovery of a body at the house, members of the community arrived to express their sadness and shock. But there was some anger directed against the family and the police.
Ginny Oteng, 46, a mother of three children, said: "I have kids of my own the same age as Tia, and I was worried because I thought there was a child snatcher out there."
Eileen Minogue, 40, said: "I feel disgusted. It is heartbreaking.
"I feel for the genuine family, her mum Natalie, the cousins and aunts who have been in that house who have had sleepless nights waiting for Tia to come home. All the while her body was there."
One man shouted abuse at the police and asked: "Weren't you watching him?"
Gavin Barwell, MP for Croydon Central wrote on his blog: "The police and forensic teams now have a serious job to do and I ask that we all please allow them to get on with trying to close a case which has, in such a short period of time, affected so many of us in Croydon and around the country.
"Despite the sad end to an emotional week, I want to praise the community in New Addington for their relentless dedication to trying to help their neighbour's family. So often in times of tragedy come inspirational displays of community."
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