A chemical factory in central Iran experienced a massive explosion on Sunday, resulting in the arrival of well over a dozen firefighting vehicles; The source of the explosion remains unknown.

Qom, located in central Iran, was rocked by a massive explosion on Sunday in one of its chemical factories, resulting in the injury of at least two firefighters. Reports indicate that upwards of 20 fire engines had to arrive on the scene to help put out the fire, consisting of approximately 150 firefighters. The particular site of interest is the Movaledan chemical factory.

According to one representative from the fire department, two of the fire engines involved caught fire following multiple explosions that occurred. Online video showed how dark smoke filled the sky in the immediate area. One of two firefighters injured in Sunday’s event remains in critical condition.

Initial reports revealed that the cause of the blast remains unknown, much like the series of explosions and fires that took place throughout the Islamic Republic in the summer of 2020. Sunday’s explosion took place during a time when tensions are on the rise between Iran and Israel. Iran blamed Israel for the series of explosions that occurred last year.