"A short while ago, the IDF began striking Hezbollah launch sites in Lebanon," the military said in a statement.

Lebanon's state-run National News Agency reported several Israeli strikes across southern Lebanon including Bint Jbeil, a symbolic town where Hezbollah said earlier it was engaging with Israeli soldiers.

An AFP correspondent saw first responders looking for survivors at the site of an Israeli airstrike that targeted the southern Lebanese village of Choukine.

In Israel, over 20 rocket alerts sounded through Thursday morning in communities near the northern border with Lebanon.

AFP footage from the border area showed long rocket trails in the sky and plumes of smoke signalling interceptions.

Calls have been mounting for the ceasefire between the US and Iran -- agreed late on Tuesday -- to be extended to Israel's war with Hezbollah, which Israel has said is not included.

Israel on Wednesday unleashed what it said was its "largest coordinated strike" on Lebanon since the war began, killing more than 300 people and wounding over 1,000, according to Lebanon's health ministry.

Hours later, Iran-backed Hezbollah said it had fired rockets towards Israel in response to what it called a violation of the US-Iran truce.