A mysterious explosion that led to a large fire inside a building in the Natanz nuclear compound was reported Thursday by Iranian officials. No casualties were reported in the incident. According to the Atomic Energy Organization of Iran, the damage was restricted to an “industrial shed” that held no radioactive material. Natanz is the largest uranium enrichment facility in the country and in recent years has been a target of several cyberattacks and computer viruses alleged to have been developed in Israel. The recent incident follows a larger explosion last Friday near Tehran. While the Iranian government blamed the event on a “gas leak,” Western intelligence analysts identified the site as an underground missile production complex.