Explosions were heard in the Iranian capital, Tehran, as Israel launched a preemptive strike. Israel is under a state of emergency, as Iran retaliated Friday night with missile attacks.

The Israeli military said Iran launched retaliatory strikes throughout the night. This followed a major Israeli attack on Friday, targeting Iran's nuclear facilities and killing top military leaders.

Although Iran maintains that its nuclear program is for peaceful energy purposes, Israel has long seen it as a threat. Israeli strikes have hit three of Iran’s nuclear facilities — Natanz, Isfahan and Fordow. Little damage appears visible in satellite imagery of Fordow.