Tens of thousands of dollars of damage was done to a shop destroyed by fire in the Tonga capital, Nuku'alofa, on Saturday.
The cause of the fire in the large Asian-owned business has not yet been confirmed.
Radio Tonga said the cost of the damage had been put at $US440,000.
Police said a man was being held in custody on suspicion of theft after he was apprehended outside the shop at the time of the fire.
The fire came two weeks after an attempted robbery on the same business during which a vehicle was driven right into the shop.