The Guard said the fire erupted Sunday in a warehouse at what it described as a “research self-sufficiency center” west of the capital, Tehran. At least three Guard members were injured, two of whom later died. The statement did not provide any further details.

The powerful Guard runs the Research and Self-Sufficiency Jihad Organization, which the U.S. Treasury sanctioned in 2017 over its work “researching and developing ballistic missiles." It wasn't immediately clear whether the site struck by Sunday's fire was involved in missile development.

There was no immediate footage of the blaze on social media or other reports pinpointing the site of the fire, although the Guard runs many facilities on the outskirts of Tehran.

Missile and other sensitive sites in Iran have seen fires before. The most notable came in 2011, when a blast at a missile base near Tehran killed Revolutionary Guard commander Hassan Tehrani Moghaddam, who led the paramilitary force’s missile program, and 16 others. Initially, authorities described the blast as an accident, though a former prisoner later said the Guard interrogated him on suspicion that Israel caused the explosion.