A British man who went on trial yesterday for killing his American wife and child allegedly told investigators that he became “trance-like” after covering their bodies with bedding.

The prosecution said that Neil Entwistle, 29, an unemployed IT worker from Worksop, Nottinghamshire, told a Massachusetts state trooper that he found his wife, Rachel, and nine-month-old daughter, Lillian, dead when he returned home from running an errand.

“After I came home and found them in the bed, I covered them up,” Mr Entwistle allegedly told Trooper Robert Manning. “It was like I was closing them off. It was all trance-like and ordered after that. My first thought was to go downstairs and get a knife from the kitchen to hurt myself, but I knew that would hurt.”

Mr Entwistle faces life in prison without parole if convicted of the murder of his wife and child in the Boston suburbs on January 20, 2006.

The postmortem examination found that Mrs Entwistle was shot in the forehead at close range and Lillian was killed with a bullet that passed through her abdomen and lodged above her mother’s left breast as she cradled her.

Mr Entwistle was arrested after flying on a one-way ticket to Britain the day after the killings. He has pleaded not guilty. The prosecution said that Mr Entwistle had told an investigator by phone from Britain that he saw a bullet hole when he found his wife and daughter dead.

But Michael Fabbri, for the prosecution, said that the bullet hole was not visible because the baby’s chest was covered by her mother’s arm. “There is only one true verdict in this case and one murderer in this case and that is the defendant,” Mr Fabbri said.

Mr Entwistle’s mother, Yvonne, sobbed quietly as the defence lawyer recounted her son’s courtship and marriage to the woman he met at the University of York. “They were devoted to each other from their first days together at York university, where they were teammates on the crew boat.” Elliot Weinstein, the defence lawyer, cautioned jurors: “The evidence you are going to hear is going to be sordid, it’s going to be gruesome, and it’s going to be graphic. Do not be overwhelmed.”

But he added: “The evidence will show you that Neil is not responsible for killing Rachel or for killing Lillian.”

The prosecution alleges that Mr Entwistle had a secret life looking for sex onlineand, unable to find a job, was struggling with debts. Mr Entwistle is fighting to stop jurors seeing a photograph of a naked, aroused man on a lounge chair that was apparently posted on the internet. The defence motion said: “The photograph does not depict Mr Entwistle.”

Court papers said that analysis of his computer showed that he visited Adult Friend Finder, an internet swingers website, “on numerous occasions” and allegedly solicited sexual liaisons on the site. The last time that he logged on to the site was January 18, two days before the killings.

The defence has complained that he cannot get a fair trial in the Boston area because the jury pool is “infected” with prejudice by the pretrial publicity.” Mr Entwistle’s fears were heightened this week by the disclosure that potential jurors joked that they should “fry him” and “send him away”.

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