Unidentified gunmen shot dead six people, including a brother of the district chief, in restive southeastern Khost province, bordering Pakistan, on Sunday morning, official and residents said.

Mohammad Younus, the Ismail Khail Mandozai district chief, said the gunmen mounted an attack on the home of his counterpart for Spera town, Mohmmad Azim, in Lalmai area. Six individuals were killed on the spot.

He said Khalil -- a brother of Mohammad Azim -- was also Dwamanda district mayor. He was assailed along with his five bodyguards as they strolled in a garden next to the official's residence.

Residents of the area confirmed the incident. No one has so far claimed responsibility.