SHEVAUN PENNINGTON thought that she was being whisked away on a romantic adventure with the punk rock fan she described to schoolfriends as her “American boyfriend”.

Little did the 12-year-old girl from Wigan know that Toby Studabaker, a former Bible school student, former US Marine and widower, was a user of child pornography suspected of impropriety with young girls.

As the unlikely couple toured Europe, Mr Studabaker saw television coverage about his abduction of Shevaun and contacted the FBI for advice. He appears to have persuaded the girl to sign a letter denying that he harmed her, then let her fly from Germany to Manchester before armed police arrested him in Frankfurt.

The story of how the disturbed US war veteran tricked a Lancashire schoolgirl into starting a relationship proves again how easily paedophiles can deceive children using the internet. But this time the British police outwitted the potential child molester by subjecting him to high-tech mind games of their own. After consulting FBI and British psychological profilers, detectives employed an ambitious strategy to manipulate the pair by controlling media coverage.

They hoped that planted reports would be seen by Mr Studabaker and Shevaun, either on satellite news coverage in a hotel room or websites in an internet café.

Journalists were told the full background to the case on condition that they reported nothing until the girl was found safe and well. The media were urged to shield Shevaun from their knowledge that her companion was a child sex pest in case she believed that he was being victimised and agreed to hide with him.

Police also begged the press not to alert Mr Studabaker that the FBI had found paedophile images on his home computer for fear that the former US Marine might panic and harm the girl. As part of the trap, Shevaun’s mother, Joanne, sent a carefully crafted message to her daughter, saying that she would be happy for the child to bring her boyfriend home.

The strategy worked. The capable Shevaun put herself on a flight from Stuttgart to Manchester, via Amsterdam, before joining her parents at a police station in Leigh, Lancashire.

Meanwhile, Mr Studabaker was ambushed in a bustling shopping centre near the US consulate in Frankfurt by armed police. He faces possible extradition to Britain for abducting a child.

Shevaun is one of unknown multitudes of children who spend their spare time in cyberspace befriending invisible strangers. Although her mother tried to restrict her internet sessions on the kitchen-table computer to five hours at a time, police discovered she would often spend 11 hours at her screen.

In chatrooms where users are required to hide their identities behind bogus nicknames, she met Mr Studabaker a year ago, around the time his wife, Jenny, died of cancer. The Studabakers were childless.

The bond between girl and man became closer. They exchanged e-mails and letters. An “American friend” began calling Shevaun at Lowton Community High School. Mr Studabaker would spend six hours a day on the net, sending pictures of himself to his admirer.

Profilers have studied the huge number of messages between the pair for clues to their thoughts. “They have developed a very strong relationship. They love each other and have strong feelings for each other,” a source said.

“These two people have meticulously planned this for some time. It was not a rushed operation. Shevaun is infatuated with this individual and the relationship between them, for their part, is intense. She cannot see anything wrong with Studabaker.

“He is an individual who is interested in child pornography. No matter what people might think about Toby Studabaker and Shevaun meeting on the internet, in their minds they have a relationship and it is intense.”

Mr Studabaker, 31, is a troubled individual. He grew up in the small Michigan town of Constantine, close to the Canadian border. In 1993-94 he attended a six-week course at Rosedale Bible College, a small Mennonite institution where he mingled with future pastors and missionaries.

In May 2000, his life took a new turn when he joined the Marines for reasons he has said he would “rather not discuss”. He trained in North Carolina with an anti-terrorism unit, the 4th Marine Expeditionary Brigade, learning to use shoulder-launched multi-purpose assault weapons.

The attacks of September 11, 2001, made his skills suddenly significant in the war against terrorism. He was a burly, shaven-headed tough guy, and photographs of him guarding al-Qaeda suspects at Kandahar airport, in Afghanistan, in December 2001 were used by media throughout the world. He was awarded the Sea Service Medal and National Defence Ribbon.

But there were question marks over his character. His brother’s wife, Sherry, said: “Toby is a very harmless person. He loves children. He would give a kid a dollar if they needed it.” However, it was for allegedly giving a nine-year-old girl a “sex lotion” that Mr Studabaker found himself under investigation at one time before officers decided no offence had been committed. In 1998 he was charged with touching the breasts and legs of a 12-year-old girl, although there was not enough evidence to proceed. Mr Studabaker was married when both incidents were alleged to have taken place.

After being discharged from the Marines with a shoulder injury, he told relatives that he was flying to Europe to meet his 19-year-old girlfriend and trace his Irish roots.

Meanwhile, in Wigan, Shevaun was asking her mother for her passport, claiming she needed proof of identity to get a travel pass because she was tall for her age. On Saturday at 7.30am, Shevaun slipped the passport into a holdall, waved goodbye to her parents and said she was going shopping with friends.

Mr Studabaker, wearing a punk rock T-shirt saying “GBH” and sporting a fresh, pudding-basin hairstyle, wheeled his suitcase through Manchester airport after a transatlantic flight.

The pair met in the flesh for the first time. They flew to Heathrow, then to Paris Charles de Gaulle. By the time French police were alerted on Monday, it was Bastille Day and the trail was lost. It is not clear if the Office for Missing Persons did much more than watch airport television footage, speak to airlines and check electronic transactions. The gendarmerie were never involved.

Having spent much of Tuesday denying that the girl had entered France, the French police then wasted time by wrongly claiming that she might have flown from Paris to Liverpool. David Blunkett, the Home Secretary, telephoned his opposite number, Nicolas Sarkozy, and told him in friendly tones that he hoped the French shared the British view that the case was extremely urgent.

As the story was picked up on television, a nervous Mr Studabaker telephoned his family in Michigan, claiming Shevaun had lied about her age, which made him “very, very mad”. Police believe that he was lying and knew that she was 12.

Relatives urged him to contact the FBI and an exit strategy was carefully prepared under which Mr Studabaker would deliver the girl to safety. It is not clear whether he told Shevaun that their adventure was coming to an end. When she telephoned her mother late on Tuesday night she showed no enthusiasm for coming home. Instead, she reinforced her commitment to her supposed boyfriend.

At the same time, Greater Manchester Police were receiving more worrying intelligence from America: there was child porn on Mr Studabaker’s computer.

Police called back the psychological profilers, asking them to get inside the mind of an infatuated 12-year-old internet addict and a scared, religiously-minded paedophile. They emphasised the importance of controlling the media images Shevaun and Mr Studabaker would receive.

A source said: “We do not know the dynamic if Shevaun discovers that he is interested in child pornography. She would never believe it anyway. She would think that the police were trying to discredit the man she loves and she would choose to go with him whatever.

“It can go to extremes of them trying to change their identitities, going deeper into this relationship, making it far harder for the police, and people working with the police, to actually get to them.”

Many viewers may have been surprised by the words of Shevaun’s mother on television yesterday morning.

“I understand that she’s got feelings for him and he may have feelings for her,” she said. “I’m actually quite relieved that he’s still with her in a way, because he’s obviously helping to look after her. As long as she comes back, she can even come back with him, I’m not bothered. I just want her back.”

This fiction was designed to lure Shevaun into a false sense of security. It worked. She telephoned her parents and said she was coming home.

“It was fantastic,” her mother said last night. “She knew she was wanted here. It was a good phone call, the best one I’ve had, ever.”

Mrs Pennington’s first words on being reunited with her daughter were. “How are you?” and “Give us a hug”.