He took revenge for jalianwallah bagh massacre in pre partition days. he was 13 at that time. He saw the incident. he grew up and went to London. he worked as a driver too. he shot dead former Punjab governor Michael O dayer in coxton Hall where he was on the dias along with other dignitoties. He shot from a very close range with an heavy 0. 455 revolver and dyer died on the spot. Lord Zetland was badly injured. udham singh was arrested and tried and sentenced to death. he was hanged in pentinvelle prison and buried there. his remains were brought back to India when zail singh was the president and cremated with honor. A dist has been named after him.