Keshubhai Nathabhai Bhalani (70) and his brother (55) Mansukh, died on the spot, the police said, adding that their sons also sustained serious injuries after which they were rushed to the Rajkot Civil Hospital.
Their condition is stated to be critical, police said.
Keshubhai and his brother had sold land to others, apparently making their cousins unhappy and it might have led to the attack, police suspects.