Ian Huntley has been found guilty of the murders of Soham schoolgirls Holly Wells and Jessica Chapman and given two life sentences.
Huntley murdered 10-year-olds Holly Wells and Jessica Chapman
As the verdicts came in, it emerged Huntley, 29, had been accused of having sex with underage girls and of rape several times in the past.
Amid criticism of the vetting procedure that allowed Huntley to get a job as a school caretaker, Home Secretary David Blunkett ordered an inquiry.
Maxine Carr, 26, was given three-and-a-half years for conspiring to pervert the course of justice but cleared of two counts of assisting an offender.
She could be free and electronically tagged within 30 days, because she has already spent 16 months in jail.
Huntley was taken to Belmarsh Prison in south-east London after sentencing.
Jessica's father, Leslie Chapman, described Huntley as a "timebomb just ready to go off", adding, "unfortunately our girls were in the wrong place at the wrong time".
'Few worse crimes'
Sentencing Huntley, Mr Justice Moses said he had displayed "merciless cynicism" after killing the 10-year-old best friends.
The judge said: "You murdered them both. You are the one person who knows how you murdered
them, you are the one person who knows why."
He said: "There are few worse crimes than your murder of those two young girls".
Huntley was told he added to the families' grief by pretending to help search for the "much loved" 10-year-olds and by offering words of sympathy to Holly's father.
Later at a press conference, Mr Chapman said of Huntley: "The next time I'd like to see him was how we last saw our daughters and that was in a coffin."
He said he hoped Huntley would one day have "the guts" to publicly explain what happened on the night the girls died.
Kevin Wells, father of Holly, said he hoped the Home Office inquiry would ensure "no other families have to endure what we have over the past 16 months".
Prime Minister Tony Blair praised both sets of parents for their "tremendous dignity".
Det Chief Supt Chris Stevenson, who led the search for the girls, said Huntley was a "calculating and callous child killer".
He said only Huntley knew why he had killed Holly and Jessica, adding: "Perhaps one day he might demonstrate a sliver of humanity and explain why he did what he did on that terrible day last August."
The chief constable of Humberside Police admitted that the force made several mistakes before clearing Ian Huntley to work with children in Soham.
It is now known that North East Lincolnshire Social Services had received four complaints of underage sexual relations against Huntley in the late 1990s.
They said none of the victims wanted to make a formal complaint, so there was nothing they could do against him.
On Wednesday, the council's chief executive Jim Leivers said he welcomed the verdicts and that the council's thoughts were with the parents and families of the murdered girls.
Humberside Police said he was reported to them eight times by alleged victims, and he was also arrested once for failure to appear at court.
There were also three allegations of rape against Huntley.
One investigation resulted in a charge, in May 1998, but the case never came to court as the CPS was not hopeful of a conviction and dropped the case.
Holly and Jessica vanished from Soham on 4 August 2002.
Their bodies were found in a ditch on 17 August, after one of the biggest police operations the UK has ever seen.
As the jury returned two 11 to 1 majority verdicts on Huntley, the Wells family hugged each other and sobbed.
A hushed "yes" resounded around the courtroom but Huntley showed no emotion.
The jury also returned a majority 11 to 1 verdict on Carr's lesser charge of conspiring to pervert the course of justice.
Huntley had admitted Holly and Jessica had died at his home and he dumped their bodies, but claimed it was an accident.
In court, Huntley said Holly died after falling into his bath, and he killed Jessica by putting his hand over her mouth to stop her screaming.
But the prosecution laid out an alternative version of events - that Huntley lured Holly and Jessica into his house, possibly with a sexual motivation, and murdered them when his plan went wrong.
It said he then coldly went about destroying the evidence and trying to hide his involvement to police, press and local residents.
Carr admitted to the court that she had lied to police to provide an alibi for her boyfriend on the weekend the girls disappeared.
She had claimed to be with him in Soham, but in fact had been in Grimsby with a 17-year-old rugby player with whom she was having an affair.
She denied she even suspected Huntley had been involved in the girls' deaths, and was only trying to protect him from being wrongly accused.
Carr is also alleged to have spent years colluding with Huntley in a benefits scam for which she was about to be charged, but instead was arrested for her involvement in the Soham case.
Her lawyer Roy James said she was relieved that "the jury had now recognised that she had
no idea that Huntley had murdered Holly and Jessica".
The vicar of Soham, Rev Tim Alban Jones, was among community leaders who said the town would be relieved that a verdict had been reached.
"If it's difficult for the people of Soham it's been far more difficult for the families of Holly and Jessica. This will perhaps be something of a watershed," he said.
When told about Huntley's past contact with the police and social services, Rev Alban Jones said had that been known he would not have been employed at the school.