An investigation is underway to determine what caused a deadly explosion at a Quebec fireworks factory Thursday morning.

Two female employees were killed in the blast at B.E.M. Fireworks in Coteau du Lac, about 60 kilometres west of Montreal. Their bodies were later found in the rubble.

The women were identified Friday as Francine Lacroix, 47, and Nicole Brisson, 58.

The Surete du Quebec offered little information about the explosion Thursday. Now, provincial investigators are planning to examine the wreckage in detail in hopes of finding out what went wrong.

The 40-year-old factory did not have a sprinkler system and police said there is no municipal water in the area, which hampered efforts to extinguish the fire.

More than 100 firefighters from different departments had to fill pumper trucks and drive to the site. Witnesses said the fire spread from a small building to a larger warehouse.

In an interview with CTV Montreal Friday, Coteau du Lac Mayor Robert Sauve questioned whether fire hydrants or a sprinkler system would have made a difference after the powerful blast.

Sauve said the factory is located in an agricultural area, so a lack of nearby fire hydrants is not unusual.

The factory was likely well-stocked with fireworks in preparation for St. Jean Baptiste Day and Canada Day. Fireworks were heard going off hours after the initial blast.

B.E.M. Fireworks manufactured their product at the plant for over 25 years.

Investigators said Friday it could take them months to determine the cause of the explosion.

Quebec’s workplace health and safety board has also launched an investigation.

With a report from CTV Montreal’s Aphrodite Salas