Air raid sirens sounded across cities in northern Israel on Thursday and Israeli officials said about 40 rockets had been fired from Lebanon in the afternoon.

State broadcaster Kan aired footage of numerous mid-air interceptions of rockets above Israeli towns, including in Safed, some 12 km (7.5 miles) from the border.

Two people were wounded by shrapnel, Israel's national ambulance service said.

Iran-backed Hezbollah opened a second front against Israel shortly after Hamas' Oct. 7 assault on southern Israel that triggered the war in Gaza. The Israel-Lebanon border has seen increasing attacks in both directions since.

The violence escalated this week with Hezbollah firing even more rockets as part of a retaliation for an Israeli strike that killed one of its senior field commanders.

Washington on Thursday expressed concern that fighting along the Israel-Lebanon border could spiral into a full-out war and called for new security arrangements.

(Reporting by Ari Rabinovitch; Editing by Angus MacSwan)