February 11, 2008—Firefighters battle a blaze at South Korea's 610-year-old Namdaemun gate.

Police arrested a 70-year-old man suspected of setting the fire that destroyed the country's top cultural treasure, according to Korean news reports.

Police had said earlier Monday that the cause of the blaze was unclear, but officials said arson was suspected.

The fire broke out Sunday night and burned down the wooden structure at the top of the stone gate, which once formed part of a wall that encircled the South Korean capital of Seoul.

About 360 firefighters fought to bring the blaze under control, according to Lee Sang-joon, an official with the National Emergency Management Agency. No one was injured, he said.

Police found a backpack and an aluminum ladder at Chae's house that witnesses claimed the man was carrying at the scene, according to the Yonhap news agency. A bottle of flammable liquid thinner was also found in his house, the news report said.

An official at the police station handling the case would not confirm the report.

Lee Keun-bae at the National Emergency Management Agency said he was aware of Chae's arrest from news reports but police had not officially notified his office of the arrest.

Firefighters found two disposable lighters at the spot where they believed the fire broke out, Yonhap reported earlier, citing fire official Oh Yong-kyu.

The two-tiered wooden structure was renovated in the 1960s, when it was declared South Korea's top national treasure. The Cultural Heritage Administration said it would take at least three years to fully restore the gate and would cost about 21 million U.S. dollars.

—Kwang-tae Kim in Seoul, Associated Press

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