Rockets are understood to have been fired from Lebanon towards Israel prompting a response.
The rockets were fired from near Seddiqine, a village in the region of Lebanon’s southern coastal city of Tyre, security sources said.
Sirens warning of incoming rockets had sounded in Israel’s lower Galilee region, east of Haifa.
The Israeli military said it is shelling a “number of targets” following the fire.
Israel’s missile defences intercepted one of the projectiles and “the rest most likely fell in open areas”, the military said.
The rockets caused air raid sirens to blare in the northern Israeli city of Haifa and areas to the east.
Security sources in Lebanon confirmed that four rockets had been launched towards Israel from Seddiqine, a village in the region of Lebanon’s southern coastal city of Tyre.
It was not immediately clear who had fired the rockets, and there were no reports of damage on either side.
It was the third incident of rocket fire from Lebanon since hostilities between Israel and Palestinian militants in Gaza flared up on May 10.
On Monday, six shells were fired from Lebanon towards northern Israel but fell short of the border, drawing retaliatory Israeli artillery fire. Three rockets launched towards Israel on Thursday landed in the Mediterranean Sea, causing no damage or casualties.
Israel fought a war in 2006 against Hezbollah guerrillas, who have sway in southern Lebanon and access to advanced rockets. The border has been mostly quiet since then.
Small Palestinian factions in Lebanon have fired on Israel sporadically in the past.
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