Soham murder suspect Ian Huntley told a BBC producer the police thought he had killed Holly Wells and Jessica Chapman, the Old Bailey has heard.
Ian Huntley is accused of murdering Jessica Chapman and Holly Wells
Debbie Tubby said the caretaker told her the police had searched his house and believed he was the last person to see the girls alive.
Four days after they went missing he asked if the police had found the girls' clothes, Miss Tubby said.
Mr Huntley denies murdering the girls, who disappeared in August 2002.
But he admits conspiring to pervert the course of justice.
His former girlfriend Maxine Carr denies helping an offender and conspiring to pervert the course of justice.
The two schoolgirls went missing after a family barbecue at the Wells' home on 4 August. Their bodies were found 13 days later in a ditch near RAF Lakenheath in Suffolk.
The jury also watched tapes of television interviews given by Mr Huntley and Ms Carr to Sky News on 15 August.
Mr Huntley said he had been the last person to see the girls, while Ms Carr described them as lovely and bubbly.
Earlier, Pc Tim Cleary told jurors how Mr Huntley had seemed to have "a great sense of guilt, that he could have done more when he met the children".
He also said they had discussed other child murder cases including Sarah Payne and Milly Dowler, who was then still missing.
Scottish journalist James McKillop, of the Herald, told the court how he had gone to Mr Huntley's house with other reporters on 8 August.
Mr Huntley had been "choking back the tears, his eyes were welling" when he described seeing the girls on the night they disappeared, Mr McKillop told the court.
"It was as if they had just dropped off the face of the world", the reporter claimed he said.
On Tuesday the court heard how Ian Huntley told a friend he believed Holly Wells and Jessica Chapman were dead, three days after they went missing.
Salesman Martin Mahoney, who sold cleaning products to the school and knew Mr Huntley as Ian Nixon, said he commented on "the awful business" when he called on Mr Huntley on 7 August about some materials.
He said to Mr Huntley that police would probably find them, but the caretaker replied: "No they'll be dead."
The court also heard how Mr Huntley told a hitch-hiker that he was one of the last people to see the girls alive.
Robert Jeynes, who was picked up by the couple just outside Grimsby, said a conversation about the missing girls had set off alarm bells for him.
He said Mr Huntley mentioned a woman who had been on TV the previous night and had "supposedly" seen the girls on the Monday.
The court then heard from a series of police officers involved in the search for
Mr Huntley denies murder
Sergeant Mark Barker, leading the search, told the court how on 7 August, Mr Huntley had shown him round the school hangar but said he only had keys to one half of the building.
But the other side had been left unlocked so police were able to search the building, Sgt Barker told the court.
This was where the charred remains of the girls' clothes were found during a later search.
Later the court heard how Mr Huntley had brought up the subject of DNA with a number of officers.
He asked Special Constable Michael Kerr what the police needed for DNA evidence, to which the officer replied "hair, skin cells or saliva".
The case continues.