The night before she disappeared in the town of Purcell, Oklahoma, last week, that same neighbour had offered to let her use his telephone to order a pizza.

On Friday her body was discovered in a plastic tub in Mr Underwood’s closet. She had deep saw marks on her neck and had been sexually assaulted after her death. Police said yesterday that they believed her killer wanted to dismember Jamie’s body so that he could eat her flesh.

David Tompkins, the Chief of Police in Purcell, said: “This appears to have been part of a plan to kidnap a person, rape them, torture them, kill them, cut off their head, drain the body of blood, rape the corpse, eat the corpse, then dispose of the organs and bones.”

Police have seized hacksaws, a dagger, a wooden cutting board, barbecue skewers and meat tenderiser from Mr Underwood’s apartment, as well as a computer and a video about serial killers. Mr Underwood, 26, is expected to be charged with first-degree murder today. Tim Kuykendall, the District Attorney of Cleveland County, said that he would seek the death penalty.

“This does not appear to be a spur-of-the-moment crime of opportunity but a well-thought-out, premeditated act with months of planning and preparation,” he said, alleging that Mr Underwood had apparently begun fantasising about eating a person a year ago.

He suggested that other targets, including a woman and a boy aged 5, had been considered by Mr Underwood before he settled on the girl upstairs. The neighbour had befriended Jamie, Mr Kuykendall said. “He had a pet rat he would put on his shoulder and she would touch the rat,” he said.

The girl was last seen on Wednesday afternoon at the library in Purcell, about 40 miles south of Oklahoma City. Police believe that she died that day, after being hit several times with a wooden cutting board, then suffocated with duct tape and her killer’s hand. Her unclothed body was found in a tub, along with a towel used to soak up blood.

“Jamie was in the apartment below us the whole time,” Rose Fox, the child’s grandmother, said. “He couldn’t move the body and hide it because somebody was out there the whole time, either on the balcony smoking or standing in front of the apartment.”

Tim Bayer, the manager of the apartment complex, said that Mr Underwood liked to stand outside and watch children play. He said that Mr Underwood had kept his apartment clean. Jamie lived upstairs with her father, Curtis Bolin, a car mechanic, who had separated from her mother, Jenny, a lorry driver in Oklahoma City, several years ago. Authorities said that they became suspicious of Mr Underwood when he pulled up to a checkpoint near the apartment complex two days after the girl was reported missing.

“He just wasn’t acting right,” Kera Philippi, an Oklahoma Highway Patrol trooper, said. “The FBI took him in for questioning.”

Last night it emerged that Mr Underwood had mentioned cannibalism in his online diary, where he discussed the effects of not taking his anti-depression medication and his “dangerously weird” fantasies. “If people knew the kinds of things I think about anymore, I’d probably be locked away. No probably about it, I know I would be,” he wrote, adding that all he wanted was to “live like a normal person”.

Mr Underwood’s alleged crime will inevitably be compared to those of other American killers, including Jeffrey Dahmer, who murdered a series of young men, and had sex with their corpses before getting further gratification from dismembering them and eating their flesh. But the murder of Jamie is most similar to the case of Albert Fish, who has been called “America’s bogeyman” and a real-life Hannibal Lecter, who murdered and ate children during the 1920s.

Jamie’s grandmother said that the family was distraught, especially the child’s father, who remained under sedation. “His whole life revolved around Jamie,” she said. “This has probably destroyed him.”

GRUESOME CRIME

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