Three people were killed over a land dispute in Uttar Pradesh's Sambhal district, police said Saturday.Four people have been arrested for their alleged role in the murder, an official told IANS. A dispute over a piece of land in Sambhal's Gumthul village turned ugly Friday.The argument between Nanhu and another villager Horilal soon turned violent. Horilal with his aides Neeraj, Mahesh and Jeemat opened fire at Nanhu. Nanhu, his son Sukkhun and brother Mohanlal were killed in the firing, police said.The bodies have been sent for autopsy and four people have been arrested and booked for the murder.