The sentence was awarded yesterday by the Third Additional Session Judge, Qamar Iqbal under section 302 of IPC, the prosecution said today.
On June 14, 2010, the accused had killed a woman, her son and grandson at village Kuda Jagir following a poll-related dispute.
They attacked the woman identified as Kunnobai (55), her son Balu (35) and grandson Majboot Singh (18) when she (Kunnobai) was returning after fetching water from a hand pump. The accused blocked her way and started beating her with sticks and other weapons.
Kannubai died on the spot while Balu and Mazboot Singh succumbed to their injuries in the hospital.
Later, police registered a case against Narayan Saharia (48), Shrilal Saharia (50) Raghuvir (48), Raghua (28), Ajmer Sirdhar (38), Gyani (68), Lampai (28) and Naktu (43).
The court also imposed fines ranging from Rs 1,000 to Rs 500 against them.