London, Feb 3 A British Sikh man who wanted to "assassinate" Queen Elizabeth II on Christmas Day in 2021 and was caught on the grounds of Windsor Castle armed with a crossbow on Friday admitted to committing treason. Jaswant Singh Chail, who identified himself as an “Indian Sikh”, wanted to kill the late monarch as revenge for the 1919 Jallianwala Bagh massacre in Amritsar in a social media video that emerged soon after his arrest. Chail, 21, admitted to an offence under the United Kingdom’s Treason Act at the Old Bailey court in London. He is the first person in the UK to be convicted of treason since 1981.