Israel has assassinated the head of Iran’s armed forces as it carried out what it described as a “pre-emptive strike” on the regime’s nuclear programmes.

General Mohammad Bagheri, Iran’s chief of the military staff, was killed along with top commanders and nuclear scientists as Israel launched waves of attacks including a strike on Natanz, Tehran’s enrichment facility.

In response, Iran launched more than 100 drones, Israel’s military said.

Israel is braced for a further retaliatory attack which Tehran said would be “harsh and decisive”.

Benjamin Netanyahu, Israel’s prime minister, said the military campaign will continue for “as many days as it takes”, raising fears of all-out war.

The US confirmed on Thursday night it was not involved in the attack, which appears to have killed some of the officials in their homes.

Bagheri was the Islamic republic’s highest-ranking military officer. The strikes also killed Hossein Salami, the leader of Iran’s powerful Islamic Revolutionary Guard Corps.

Two hundred jets were deployed in the attack and 100 targets were struck, Israel said.

Israel has declared a state of emergency across the entire country ahead of an expected response from Iran that it said could come within hours.

Officials in Tel Aviv have warned that Iran could retaliate by launching hundreds of ballistic missiles.