Who was hanged for shooting a police officer in response to the killing of veteran freedom fighter Lala Lajpat Rai? (He joined with other revolutionaries, Shivaram Rajguru, Jai Gopal and Sukhdev Thapar, in a plot to kill the police chief, Scott)

Bhagat Singh was hanged in 1931 for the murder of British police officer John Saunders (not Scott as mentioned in parentheses), which was in retaliation for the death of Lala Lajpat Rai from injuries sustained during a lathi charge. The plot to kill police chief James A. Scott was a separate planned assassination that failed.