"Two Katyusha rockets were fired from a Lebanese village five kilometres (three miles) from the border with Israel" the Lebanese source told AFP.

A statement from Israel's military suggested that three rockets were fired.

"Sirens sounded in northern Israel. Initial report suggests three rockets hit northern Israel. Forces are searching the area" it said.

Across the heavily militarised frontier troops with the United Nations Interim Force in Lebanon (UNIFIL) and the Lebanese army were searching for the firing point the Lebanese source said.

The rocket fire from the Hezbollah heartland of south Lebanon followed the death of Samir Kantar a militant in the Shiite group notorious for the murder of three Israelis.

Hezbollah said the 54-year-old Kantar was killed in an Israeli air strike near the Syrian capital Damascus on Saturday night.

There was no confirmation from Israel that it was responsible for Kantar's killing.

Members of Hezbollah are fighting alongside Syrian President Bashar al-Assad's forces against insurgents who have been battling to oust him for nearly five years.