Documentary shows the moment Jon Venables admitted to killing James Bulger

A new documentary shows the moment Jon Venables admitted to killing James Bulger.

In 1993, Venables and Robert Thompson led the two-year-old away from a busy shopping and brutally murdered him.

Following their trial, the pair were sentenced to life in prison.

Channel 5 documentary James Bulger: The Trial uses witness testimony from the time to recreate scenes from the courtroom.

One segment of the heartbreaking doc shows the moment Venables told the police that he was responsible for the murder.

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The young boy is overheard saying: "I did kill him."

The confession was later played during the trial, with Venables initially telling detectives: "I can't tell you because mum will be annoyed."

However, when his mum left the interview room, he admitted: "I did kill him.

"What about his mum, will you tell her I'm sorry?"

However, his accomplice, Thompson, denied any involvement in James' murder.

"He's a liar," he said of Venables. "I never got the boy. I never killed him.

"We never killed him. I told him to take him back. Why am I getting all the blame?"

James' mum Denise Fergus fought for years to keep Venables and Thompson behind bars.

However, because they were both 10 years old at the time of the murder, they served just eight years before being released in 2001, with the pair given new identities.

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The doc shows the first time the grieving mother had seen her witness statement from the trial in 30 years.

"At the time it had come from my heart," she said, looking back.

"It's been 30 years since I've last seen this and I can't read it, I've described James in it, and I can't do it.

"I don't want to go back there, I know for a fact it's played back in my mind, if I read that I'm back to day one."

Thompson continued to deny any part in James' death at the trial, but forensic analysis of his shoe matched an injury to the toddler's head.

And while his defence team hoped that enlisting a psychologist to speak to him would help his case, it did the opposite.

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Elizabeth Vizzard told the court that Thompson clearly understood what he had done.

"He knew the difference between right and wrong," she said.

Ms Fergus said of Thompson's defence: "When my lads were growing they would have known the difference from right and wrong from a very early age.

"Are they that dumb at ten? An animal killing an animal, a child killing a child, age doesn't matter."

Venables was sent back to prison at the age of 40 after having been convicted of possessing indecent images of children.

However, he could be released in the next few weeks if his parole is granted.