According to El Universal, a fire broke out after the explosion, blocking the exit for people in the store. Several children are among the dead.
Governor Alfonso Durazo writes on X that he has ordered an investigation into the incident, which occurred around 2 p.m. local time.
According to authorities, the explosion may have been caused by a fault in a transformer in the store, writes AFP.
The news site El Universal reports that it is also investigating whether the explosion may have occurred in a vehicle outside the store's entrance. Images from the scene show fire damage to both the facade and parked cars.
Saturday's planned festivities in conjunction with the city's celebration of Día de los Muertos were canceled due to the incident.
