Rescuers work on the site of an explosion in Yanjiao of Sanhe city, north China's Hebei province, March 13, 2024. (PHOTO / XINHUA)

SHIJIAZHUANG — A preliminary investigation into the fatal explosion in north China's Hebei province on Wednesday, which resulted in seven deaths and 27 injuries, indicated that it was caused by gas pipeline leakage, according to local authorities on Thursday.

The ignition point of the accident was located within a building in Yanjiao Town, in the city of Sanhe. The building hosted a number of businesses, including a fried chicken shop, but the specific store where the ignition took place is yet to be determined, said Liu Fulai, head of the investigation team.

It is difficult to determine whether there is a single-point leakage or multiple-point leakages due to the complexity of the underground pipeline network

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The leak is below the ground surface, and precise detection efforts to confirm the exact point of leakage are underway, Liu added.

The investigation remains challenging, as it is difficult to determine whether there is a single-point leakage or multiple-point leakages due to the complexity of the underground pipeline network, said Ji Hongtu, director of the city's emergency management bureau.

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The blast occurred at 7:54 am on Wednesday. All the injured were rushed to the hospital, but their injuries are not life-threatening.