A man speaking on an iPhone 5 mobile phone narrowly escaped injury when the device overheated and exploded.
Businessman Suwicha Uasomsaksakul said he was clutching his iPhone5 and became alarmed when it became too hot to touch. He threw it to the ground, where it exploded.
Mobile operator Advanced Info Service (AIS) has been asked by the National Broadcasting and Telecommunications Commission (NBTC) to explain why the phone exploded.
Thai Rath newspaper reported on Tuesday that Mr Suwicha, 34, was in the Lak Si area when the device exploded. He was not injured.
Mr Suwicha lodged a complaint with Don Muang police station.
NBTC secretary-general Takorn Tantasit said he called AIS, a phone signal provider and importer of iPhone handsets, asking it send the damaged phone along with its battery to the NBTC office.
"We will try to finish our probe within four days," Mr Takorn said.
AIS said it was responsible for the matter and offered Mr Suwicha a new phone to replace the damaged one.
However, Mr Takorn said the NBTC needed to probe the matter to verify whether AIS had imported the device legally and whether the device matched industry standards.
He insisted his agency had the rights to regulate the import of telecom devices.