Care worker Stephen Nicholson has been found guilty of the “execution-style” murder of schoolgirl Lucy McHugh who he killed to prevent her revealing his year-long abuse of her.

The 25-year-old showed no emotion as he was convicted at Winchester Crown Court of the murder of the 13-year-old, as well as three counts of rape when she was aged 12.

Nicholson was also found guilty of sexual activity with a child in relation to another girl in 2012, who was aged 14.

He was acquitted of a charge of sexual activity with a child on multiple occasions when Lucy was aged 13.

Lucy was stabbed to death in woodland at the Southampton Sports Centre on July 25 last year.

The youngster, described as “vulnerable” because of her age and because she had been diagnosed as having ADHD, had been lured there by the defendant.

The judge, Mrs Justice May, thanked the jury for their service and adjourned the case for sentencing on Friday.

The trial heard that Nicholson, described by police as a “predatory paedophile”, had abused Lucy for more than a year while living as a lodger at her family home.

He then killed her to silence her when she threatened to reveal their sexual relationship.

She had also said that she would tell her mother that Nicholson had got her pregnant although a post mortem examination showed that she was not pregnant at the time of her death.

William Mousley QC, prosecuting, described the murder as premeditated and a “execution-style” killing.

Detective Superintendent Paul Barton, of Hampshire police, said after the trial: “I would describe Nicholson as cold and calculated, I would describe him as a paedophile and I think he is someone who only thinks about himself and has taken full advantage of this family that have looked after him, provided a roof over his head.

“He has targeted Lucy, taken advantage of her and when she wanted a relationship with him, he has taken the decision to silence her once and for all by brutally killing her.”

The investigation into Lucy’s death, described by the CPS as “one of the largest in criminal history” was hampered when Nicholson refused to give police his Facebook password.

After applying through the US courts for access to his account, prosecutors only received a log of his Facebook contacts with Lucy but not the content of any messages. It finally arrived the day that the trial started.

The defendant, who admitted dealing cannabis, claimed he had not wanted to reveal his drug contacts via his Facebook account out of fear they would attack his family.

Nicholson, a tattoo artist, was convicted of targeting another girl aged 14 who he had sex with as a trade for giving her a cheaper tattoo.

The defendant denied having an appetite for sex with underage girls and said he did not have a relationship with Lucy.

He claimed Lucy had been “stalkerish” towards him and he had been at the home of an elderly friend when she was murdered.

Nicholson was linked to the murder through DNA evidence from both him and Lucy found on clothing, described by prosecutors as his “murder kit”, which was discarded in woodland in Tanner’s Brook, about a mile from the murder scene.

He also tried to cover his tracks by inflicting wounds on Lucy that could be interpreted as self-inflicted and also posed in different clothing on CCTV at a Tesco Express store.

The court heard that Nicholson, a father-of-one, had a love for reptiles and had a collection which included 12 pythons, chameleons, geckos and corn snakes.

Nicholson also told how he enjoyed “soft choking” women during sex which involved squeezing their neck to intensify the sexual effect.