KUNMING, Jan. 17 -- A fire in an ancient town in Shangri-la, a resort county in southwest China's Yunnan Province, on Saturday was caused by a heater, local authorities said on Friday.

The blaze broke out in Ruyi Inn in Dukezong Ancient Town after its owner Tang Ying forgot to turn off the heater, causing it to set fire to a curtain, according to a statement from the fire-fighting and disaster-relief headquarters.

Tang is being investigated for negligently causing the fire, the statement said.

The fire burned over 59,980 square meters, damaging more than 240 houses, with another 43 properties having to be dismantled. The blaze caused direct economic losses of 89.83 million yuan (14.85 million U.S.dollars).

Apart from houses, shops and infrastructure facilities, the fire damaged cultural relics, Tibetan thangka and other Tibetan art.