SEOUL - South Korean police said on Sunday they booked a man suspected of starting what grew into the country's largest wildfire, killing at least 26 people and razing thousands of buildings including historic temples.

Authorities believe the man, who is in his 50s, began the fire in southeastern Uiseong county when he performed an ancestral rite by a family grave on March 22, an official from Gyeongbuk Provincial Police said.

"We are in the process of verifying evidence," the official added.

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In South Korea's legal system, booking involves registering a suspect but may not coincide immediately with arrest or charges.

Yonhap news agency said the man had denied the allegations.

The fire burned about 48,000 hectares (119,000 acres), destroyed an estimated 4,000 structures, and forced tens of thousands of people to evacuate. By Friday the blaze was largely contained although firefighters were still battling small hotspots that had sprung up on Saturday.

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The Uiseong fire as well as separate blazes across the country last week left at least 30 people dead and sparked calls for national reforms to better tackle such disasters, which experts say are being exacerbated by climate change.

The forest service said on Sunday another wildfire broke out in a southern area near Suncheonsi, and authorities had deployed 23 firetrucks, four helicopters and 123 firefighters.