A Delhi court on Saturday awarded life imprisonment to three persons for attempting to murder members of a Sikh family, during the 1984 riots, and imposed a fine of Rs 6 lakh for being involved in the crime. Mangal Sen alias Billa, Brij Mohan Verma and Bhagat Singh were held guilty of attempt to murder, rioting and dacoity in Shastri Nagar in north Delhi by Additional Sessions Judge S S Rathi on August 22.