DF forces claimed it was conducting 'precise strikes' on military targets in Tehran in response to what it called 'the continuous attacks from the regime in Iran against Israel'.
The Middle East has been on edge in anticipation of Israeli retaliation for Iran's attack on October 1, in which around 200 ballistic missiles were fired at Israel, Iran's second direct attack on Israel in six months.
An Israeli military statement said that Israel 'has the right and the duty to respond', although it did not elaborate on targets.
Adding: 'The regime in Iran and its proxies in the region have been relentlessly attacking Israel since Oct. 7 - on seven fronts - including direct attacks from Iranian soil.'
Witnesses in Tehran confirmed hearing loud explosions said: 'It was so loud and the sky became red,' said an Iranian resident in Tehran, who asked not to be named.
Shortly after communities in northern Israel were told to take shelter amid an alert of a drone from Lebanon.
The Home Front Command issued an alert for a 'hostile aircraft intrusion' around the northern city of Nahariya and other parts of Galilee.
Prime Minister Benjamin Netanyahu and Defense Minister Yoav Gallant were in a bunker at the military headquarters in Tel Aviv, Netanyahu's office said.
The Isreali Prime Minister's Office has released an image of Prime Minister Benjamin Netanyahu, Defense Minister Yoav Gallant and military officials at the IDF's underground HQ amid the strikes on Iran
There have been reports of at least seven explosions that have rocked the city of Tehran, as well as loud blasts heard in the Damascus countryside and central region.
The Israeli military said it had 'fully mobilised' its offensive and defensive capabilities as it carried out strikes on military targets in Iran, as military spokesman Rear Admiral Daniel Hagari, in a separate statement, called on the people to be 'alert and vigilant'.
Iranian authorities have warned Israel against launching an attack, saying any strike on Iran would be met with a stronger retaliation.
As its media reported that the several 'loud explosions' that were heard were related to the country's air defense systems.
As Tasmin, the Islamic Revolutionary Guard Corps (IRGC) news agency, claimed that 'no strike has happened against IRGC military centres in the west or southwest of Tehran so far'.
