A SCHOOL caretaker and his girlfriend left police stations last night after being questioned in connection with the disappearance of Holly Wells and Jessica Chapman.

Ian Huntley, 28, the site manager at Soham Village College for the past nine months, and 25-year-old Maxine Carr, a former teaching assistant in the girls' primary school class, were quizzed for seven hours at separate police stations.

Cambridgeshire Police said the couple had agreed to be questioned and had been treated as significant witnesses.

A spokeswoman said the pair had completed witness statements and were no longer with officers.

The couple will not be returning to their house, which is the subject of a detailed search using what police described as highly sensitive equipment. The house was one of the last places the ten-year-olds were seen.

St Andrew's Primary School, which the girls attend, was also being scoured for clues in a process that was expected to last several days. Meanwhile, a police helicopter hovered over the school's playing fields.

Detectives also called in help from Mark Harrison, a search specialist from Bedfordshire Police, who was involved in the hunt for missing Sussex teenager Millie Dowler and missing Essex teenager Danielle Jones.

Police, who have not named Mr Huntley and Ms Carr as the two people questioned, said the searches would go on through the night.

The couple were driven from their home in separate cars at 3.40pm. Mr Huntley went to Ely police station, while Ms Carr was questioned at Peterborough. Police said at 10.25pm they were no longer with officers.

Mr Huntley has been a witness in the investigation from day one after telling how he saw the girls at about 6.15pm on the day they vanished - about an hour before the last confirmed sighting.

He wept as he recalled to reporters a few days later how he had seen them when he was washing his German shepherd dog, Sadie, near the front door of his house.

He said: "I just saw them for a few minutes. They were as happy as Larry. They haven't run away. They didn't have a care in the world. I must have been one of the last people to speak to them.

"It seems they have just disappeared off the face of the earth. How can two girls go missing in broad daylight, then nothing? No sighting. No nothing. It beggars belief."

Ms Carr, who recently failed to obtain a full-time teaching job at the school, also spoke to reporters, telling them last week: "On the last day of school, Holly gave me a card with a smiley face on the front and a poem inside. She was crying because I didn't get the job."

The searches were launched hours after Detective Chief Inspector Andy Hebb told reporters: "I do believe the piece of the jigsaw we are looking for lies in or very close to Soham."

A police spokesman said last night: "We remain as optimistic as we were at the start of this inquiry that we will find Holly and Jessica alive. We are clearly entering a critical stage in this inquiry. We are determined to find Jessica and Holly and will not cease our work until we find them."

The couple gave police permission to search their detached home in the grounds of the college.

Mr Huntley had only begun work at the college within the past nine months when he was known as Ian Nixon, the local education authority said last night.

He changed his name two or three months ago "for family reasons", said a county council spokesman.

He had not worked as a caretaker before but had held a number of jobs, mostly in the Lincolnshire area.

Mr Huntley was the senior site officer at the college, in charge of three others.

Ms Carr began work at St Andrew's on a voluntary basis in February. She continued until Easter when she was awarded a short-term contract as a teaching assistant.

* Three specialists from Durham Police are joining the inquiry. They will help operate a complex computer system in a bid to locate the ten-year-olds