A prominent Bosnian Serb businessman has died in what local media have described as a mafia-style execution.

Slavisa Krunic, who owns several businesses including a private security firm, was killed in his vehicle late Monday as he approached his family home outside the northern Bosnian city of Banja Luka. Krunic is known as a vocal critic of the ruling nationalist party.

Krunic's bodyguard and one of the attackers were also killed. His driver sustained serious injuries, police said.