A fire and explosion at a convenience store in northwestern Mexico on Saturday killed at least 23 people, including children, and injured 12 others, state authorities said.

The fire occurred in downtown Hermosillo, the capital of Sonora state, Sonora Gov. Alfonso Durazo said in a video posted on social media.

“The explosion at the "Waldos" store in the Centro neighborhood of Hermosillo has left a deep sadness among all Sonorans,” he said.

Sonora Attorney General Gustavo Salas Chávez provided the death toll and said the injured were taken to six hospitals in Hermosillo.

Salas Chávez said preliminary investigations showed the deaths were caused by “inhalation of toxic gases.”

“At this time we have no indication that leads us to presume the fire was intentional,” he said, noting authorities had not ruled out any line of investigation.

AP Video by Abraham Téllez