Before Israel launched an unprecedented wave of strikes against Iran’s nuclear facilities and top military leaders this week, its spies were already on the ground in enemy territory. Israeli intelligence agency Mossad had smuggled weapons into Iran ahead of the strikes,

The two powers have been exchanging barrages since Israel attacked Iran early Friday and killed many of the country’s top military leaders and scientists.

Iran has launched retaliatory missile strikes on Israel into Saturday morning after a series of blistering Israeli attacks on the heart of Iran’s nuclear program and its armed forces, killing at least three people and wounding dozens.