No casualties or damage to the house were immediately reported.

Police suspect that the fire might have been caused by a discarded cigarette thrown by a reserve soldier who had a training session on the hill. They said a reserve force training group discovered the fire soon after the previous group's training exercise.

But police authorities said since there are mountain trails nearby, they will also look into whether the fire was started by a hiker.

Police said although the fire appeared to be accidental as no inflammable substances were founded on the hill, they will not rule out the possibility of arson.

A memorial hall inside the house was once burnt by an arsonist in December and restored late last month.

Park Chung-hee ruled the country for 18 years until he was assassinated in 1979. He seized power in a military coup in 1961.

He is credited with laying the foundation for the country's dramatic economic growth, but has been heavily criticized for his authoritarian rule.

The incident came as his daughter was dismissed by the Constitutional Court on Friday over a corruption scandal involving her friend. Park Geun-hye is the country's first democratically elected leader to be ousted by impeachment. (Yonhap)