Additional district sessions judge Rajesh Bhardwaj also imposed a fine of Rs 1,500 on each of them after holding them guilty under IPC sections 302 (punishment for murder) and 201 (causing disappearance of evidence of offence) last evening.
The convicts are Ajit and Amit (brothers), Sundar and Sanjay.
According to government lawyer Kayyum Ali, Ratanpal was murdered by the four in August, 2004, on suspicion that he was in a relationship with the mother of Ajit and Amit.