Iranian state media is reporting that a fire at a shopping center in southern Fars Province has injured 37 people.
The IRIB broadcaster says the fire in the city of Shiraz was started by an explosion early on June 3.
The head of the fire department in Shiraz, Mohammad Farokhzadeh, told state television that a gas leak or an explosion of flammable items stored in the supermarket could be the cause. An investigation was under way, Farokhzadeh said.
Mohammad Reza Alimanesh, head of the provincial emergency organization, told IRIB that 15 of the injured were hospitalized.
None of those injured was in critical condition, Alimanesh was quoted as saying by state news agency IRNA.
The explosion was heard in most neighborhoods of Shiraz, IRNA reported, adding that walls of the supermarket had collapsed.
The explosion occurred at 12.45 a.m. (2115 GMT/UTC) in the city's Hypermarket center, the reports said.
During the Muslim holy month of Ramadan, when observers fast from dawn till dusk, shopping centers are usually busy with customers late in the evening.
In January, 26 people including 16 firefighters were killed when a building collapsed following a fire in downtown Tehran. Officials blamed it on an electrical short circuit.