The unknown gunmen barged into a house in Ali Zai area of Kohat district of Khyber Pakthunkhwa and opened firing. As a result of firing a man, his wife, two daughters and son were killed on the spot, police said.
The gunmen fled the scene after the attack.
A land dispute is behind the attack, sources said.
An investigation has been launched by the police. The bodies of the victims were shifted to the hospital for medico-legal formalities.