Iran's ballistic missiles and drones have caused explosions inside Israel in its serious wave of retaliation, midnight Friday and early Saturday, according to the Iranian Armed Forces.

The Islamic Revolution Guards Corps (IRGC) said in brief statements after the strikes that dozens of Israeli targets, including military sites and airbases, were hit in pinpoint strikes, according to intelligence collected by them.

Targets included Israeli military bases used to initiate the unprovoked strikes on Iran, as well as industrial weapon manufacturing and other military sites deep in Israel, the Islamic Republic News Agency reported.

The Israel Defense Forces (IDF), said air defenses intercepted suspicious aerial targets, which triggered sirens across the country, including in the Eilat and Arava areas, according to The Times of Israel. The casualties are yet to be confirmed, though dozens were reported as injured despite warnings of shelter taking.

Iranian Supreme Leader Ayatollah Ali Khamenei, just before the Iranian strikes began, said in a televised speech to the nation that the Israeli regime would not be able to walk away from the strikes on Iran unharmed.

"Strong action should be taken, and will be taken," the Iranian leader said. "We will have no leniency on them. Life will undoubtedly turn bleak for them".

Iranian media reported more than 100 people dead or wounded were accounted for already in Israel's sudden attacks against Iran early Friday, including in residential areas apart from nuclear sites and military facilities.