Tragic reports are speaking about an incident that struck the city of Hermosillo in the northwestern Mexican state of Sonora on Saturday.

A massive explosion triggered a fire at a discount supermarket chain called Waldo that killed at least 23 people that including young children. Nearly a dozen more were injured.

The blaze broke out in the store’s downtown location at about 2 to 3 pm local time as the city was marking the Dad of the Dead holiday weekend.

Local authorities mentioned how many of the fatalities were caused by inhalation of toxic gases instead of direct burns, as per local media outlets. The governor confirmed minors among the victims and ordered a thorough investigation to figure out what had gone wrong.

The incident seems to be accidental, and an electrical fault or transformer issue might be the leading cause of this incident. Authorities mentioned how there is no evidence of a deliberate attack.

Emergency services responded with several ambulances and staff; victims were rushed to several hospitals in Hermosillo. For now, the official cause of the fire is under investigation. Families are currently the focus of government support, with the President expressing condolences over the incident.