27-year old Sujith, a Rashtriya Swayamsevak Sangh (RSS) activist was hacked to death near Pappinisseri in Kannur district of Kerala.
Sujith's parents and brother suffered injuries when they tried to stop the attack.
The Police has taken eight people into custody and investigation is underway.
Meanwhile, the district Bharatiya Janata Party (BJP) and RSS leaders have alleged involvement by the Communist Party involvement in this attack, but the local leaders of Left parties have denied the allegation.