Israel has not commented on the attacks that killed 37 people and wounded nearly 3,000 over two days but has said it will widen the scope of its war in Gaza to include the Lebanon front.

"Such terrorist acts, that are undoubtedly due to the desperation and successive failures of the Zionist regime, will soon be met with a crushing response from the resistance front," Guards commander General Hossein Salami said in a message to Hezbollah leader Hassan Nasrallah, quoted by state media.

The resistance front led by Iran includes Tehran-backed groups across the Middle East, including Lebanon's Hezbollah, Yemen's Huthi rebels, and Shiite armed groups in Iraq as well as Palestinian militant group Hamas.

In April, Iran fired hundreds of missiles and drones at Israel, after it bombed an annexe of the Iranian embassy in Damascus, killing seven Revolutionary Guards, two of them generals.

Most were intercepted by Allied air forces or Israel's air defences.