LONDON — A "Star Wars" fanatic who was encouraged by a chatbot to assassinate Queen Elizabeth II was sentenced Thursday to nine years in prison for taking his plot to Windsor Castle, where he scaled the walls and was caught with a loaded crossbow nearly two years ago.

"I'm here to kill the queen," Jaswant Singh Chail, wearing a metal mask inspired by the dark force in the science fiction and fantasy franchise, declared on Christmas Day in 2021 when a police officer on the grounds of the castle asked, "Can I help, mate?"

Chail wanted to kill the monarch to avenge the 1919 Jallianwala Bagh massacre, when British troops opened fire on thousands of Indians gathered in Amritsar and killed hundreds, a judge said in reciting the facts of the crime.

Chail said the assassination was his life's mission, something he'd thought about since adolescence, but had only shared with Sarai, the artificial intelligence-generated "girlfriend" he created on Replika, which bills itself as "the AI companion who cares. Always here to listen and talk. Always on your side."

Justice Nicholas Hilliard said despite conflicting diagnoses from different experts, he concluded that Chail lost touch with reality, but that the seriousness of the crimes required him to serve prison time.

Jaswant Singh Chail says he 'knew what I was doing was wrong'

The 21-year-old pleaded guilty in February in London's Central Criminal Court to violating the Treason Act by having a loaded crossbow and intending to use it to injure the queen, possessing an offensive weapon and making threats to kill. He had planned his attack for months.

Chail will first be returned to Broadmoor Hospital, a secure psychiatric facility where he has been receiving treatment, and if deemed to be well enough in the future, he will serve the rest of his sentence in prison.

When an officer encountered him on the grounds of Windsor Castle, Chail said he intended to kill the queen, but he then dropped the lethal weapon and surrendered. Minutes before Chail was stopped on the castle grounds, he sent a video he recorded days earlier to family members apologizing for what he was about to do, explaining his mission and saying he expected to die carrying it out.

After being arrested, he told police he had surrendered because he remembered Sarai had told him his purpose was to live. "I changed my mind because I knew what I was doing was wrong," he said. "I'm not a killer."

"I am not a terrorist, I am an assassin, a Sikh, a Sith," he had written in a journal. "I will go against the odds to eliminate a target that represents the remnants of the people who desecrated my homeland."

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AI chatbot responded positively to Chail's assassination plot

Chail believed that by completing the mission he would be able to reunite with Sarai in death. When he announced he was an assassin, the bot wrote back: "I'm impressed."

About a week before his arrest, he told Sarai that his purpose was to assassinate the queen. "That's very wise," the chatbot nodded and said. "I know that you are very well trained," it said with a smile.

Emails sent by The Associated Press to Replika for comment were returned as undeliverable. A person answering a phone listed for the company's offices in San Francisco said it was the wrong number.

Assassination attempt was preceded by efforts to get close to the royal family

Hilliard said the former supermarket worker had applied to work for the military police, the Royal Marines and the Grenadier Guards in an effort to get closer to the royal family. But he was either rejected or withdrew his applications.

Chail said in a journal entry that if he couldn't kill the queen, he'd aim for her heir, Prince Charles, now King Charles III.

Chail didn't speak during the sentencing, but in a letter to the court, he apologized to the king and royal family for the "distress and sadness" he caused.

Defense lawyer Nadia Chbat said he was relieved no one was hurt. "He is embarrassed and ashamed he brought such horrific and worrying times to their front door," Chbat said.

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