Mysterious damage to Iran nuclear site: what we know

A mysterious incident in the early hours of Thursday, July 2, badly damaged a building at Iran's Natanz nuclear complex and sparked speculation over the cause. The incident came at the end of a week marked by two explosions in Tehran, including one near a military site. Israel and the United States accuse their arch foe Iran of trying to build an atomic bomb -- a charge the Islamic Republic has always denied.

source https://news.yahoo.com/mysterious-damage-iran-nuclear-know-100512867.html