A fire destroyed two large shops, one selling plastic goods and the other motorcycle accessories, in the heart of Muang district in the early hours of Thursday.
There were no casualties, but total losses were initially estimated at 60 million baht.
The fire began in the Chamras Plastic shop and spread to the adjoining Ood motorcycle accessory shop, on Pitakchart Road in Muang municipal area.
The blaze was reported about 1.40am, Pol Capt Rattanaporn Thongcheen said.
More than 20 fire trucks and crews from the Muang municipality and nearby areas were dispatched to the scene. By the time they arrived the flames had a strong hold on the two-story commercial building.
It took firemen about four hours to bring the fire under control. Both shops, each the size of two stores, were gutted. There was no-one insde at the time the fire started.
Supattra Sutthiwichaiporn, 38, owner of Chamras Plastic, said her shop had been trading for many years. Each night she would leave five lights turned on inside the shop when she left. Nobody stayed inside.
She did not know what could have caused the blaze. She had not lit any candles or joss sticks. The fire caused about 50 million baht in damages, to her shop and destroyed goods, she said.
The shop was insured, but she was no sure whether it would cover the full cost of the loss.
Damage to the Ood motorcycle accessory shop was estimated at 10 million baht.