Maxar Technologies released satellite imagery on Sunday showing activity at Iran's Fordo nuclear facility prior to U.S. air strikes.

Those bombs were widely seen as the best chance of damaging or destroying Fordo, built deep into a mountain and untouched during Israel’s weeklong offensive.

Iran’s most heavily fortified nuclear site is at Fordo, a hilly area south of Tehran and about 15 miles away from Qum, a city where more than a million people live.