Mexico City, Mexico - Mexican President Claudia Sheinbaum expressed horror and gave her condolences after a massive explosion at a supermarket in northern Mexico killed at least 23 people on Saturday.

An explosion at a Waldo's supermarket killed at least 23 people in the northern Mexican city of Hermosillo on Saturday, according to local officials.

In a Saturday post on X, translated from Spanish, Mexican President Claudia Sheinbaum expressed her condolences "to the families and loved ones of those who died."

"I have been in contact with the Sonora governor, Alfonso Durazo, to provide support as needed," Sheinbaum wrote. "I've instructed the Secretary of the Interior Rosa Icela Rodríguez to send a support team in order to assist the families and the injured."

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Video taken at the scene shows huge flames engulfing the building as well as a number of cars parked close by. Black smoke is billowing from the building in the clip, and people are seen walking around as if in a daze.

"Sadly a number of the victims we've found were minors," Alfonso Durazo, governor of Sonora state, said in a video message.

"I have ordered an extensive and transparent investigation to determine the causes of the incident and figure out those responsible," he said.

The prosecutor's office said in a statement that "the working assumption is that the incident was accidental, and the investigation is looking into a transformer located inside the store."

"Once the firefighters allow access into the building," the statement read, "It will be possible to precisely determine the cause of the incident."

Mexican media reports said customers sought refuge inside the store after the explosion, only to become trapped by the flames.

"Nobody will face this pain alone. From the very first moments, emergency, security and health services responded with great professionalism and commitment, controlling the situation and saving lives," Durazo said.