Israeli authorities are investigating the failure of its famed Iron Dome defence system to intercept rockets fired from southern Lebanon that killed two Israelis on Wednesday.
Iron Dome interceptors have taken out hundreds of rockets fired by Lebanese Shia militant group Hezbollah, which began its armed campaign against Israel last October in response to the assault on Gaza.
Israeli emergency services said a man and a woman in their 40s were hit by shrapnel in the border town of Kiryat Shmona - the first Israeli civilians to be killed by rocket fire since Israel escalated its bombing of Lebanon two weeks ago.
The attack followed a suspected Hezbollah strike on Israel's third largest city of Haifa, which saw five people injured in the second hit on the city in less than a week.
The Israeli army said some 40 rockets were fired towards Haifa on Wednesday, which caused five Israelis to suffer minor injuries from shrapnel, in another failure by the Iron Dome to intercept Hezbollah rockets. An attack last Friday on the port city caused damage to a road and minor injuries to civilians. Hezbollah claimed earlier to have targeted a military base north of the city.
The military claimed to have hit the launchers which fired the rockets at Kiryat Shmona later on Wednesday.
Hebrew-language media reported that Israeli authorities are investigating why the missiles were not intercepted by the missile defence system. The incidents will likely have spooked military officials who boast of its sophisticated capabilities and promote the Iron Dome to the public as the country's key aerial defender.
The Iron Dome system has taken out missiles fired by Hezbollah in Lebanon, the Houthis in Yemen, the Islamic Resistance groups in Iraq, Hamas in Gaza, and more recently, Iran.
The air defence system has batteries situated across Israel which hold multiple interceptor missiles and said to be the "most-combat-tested" air defence system in the world. It is partly supported through US military aid to Israel.
Thousands of residents on both sides of the border have been displaced by the year-long cross border fire which escalated after Israel launched a ground invasion into the southeast and southwest border areas in late September.
The Israeli government has rejected US-led calls for a temporary pause in fighting despite the escalating Lebanon death toll and wider displacement.