BEIRUT/JERUSALEM (Reuters) - Israel carried out heavy airstrikes in south Lebanon and Hezbollah said it had launched explosive drones and rockets at Israeli targets on Wednesday as Israel's defence minister warned of a "hot summer" in the border region.
The Israeli attacks killed three Palestinian fighters from the Quds Brigades, the armed wing of the Islamic Jihad movement, according to the group. Hezbollah said at least one of its fighters was also killed.
Israeli attacks killed three people in Lebanon, security sources said.
The conflict between Hezbollah and Israel has rumbled on since October in parallel to the Gaza war, uprooting tens of thousands of people on both sides of the frontier and fuelling concern of a bigger war between the heavily-armed adversaries.
The Israeli military said it had hit military structures and infrastructure belonging to the Iran-backed Hezbollah in three locations in south Lebanon, including more than 20 strikes on Hezbollah targets in the Ramyeh area.
Hezbollah said it had launched explosive drones at a military headquarters in the Israeli border town of Ya'ara, and fired its powerful Burkan rockets at a barracks in Biranit, among at least 10 attacks announced by the group on Wednesday.
Lebanon's National News Agency reported Israeli strikes on 28 towns and villages of south Lebanon, a Hezbollah stronghold. Two security sources in Lebanon said the Israelis were using powerful munitions in an apparent attempt to hit Hezbollah underground bunkers.
The Israeli military said secondary explosions had been identified during the attack by its artillery and warplanes in the Ramyeh area, indicating there were weapons storage facilities in the location.
The displacement of some 60,000 residents of northern Israel has prompted calls within Israel for firmer military action against Hezbollah. Across the border in Lebanon, some 90,000 people have also been displaced by Israeli strikes.
Israeli Defence Minister Yoav Gallant, speaking to troops during a visit to northern Israel, said the mission was not complete.
"This summer may be a hot summer," he said in a video message issued by his office.
He said that either a diplomatic agreement or a military solution was needed for residents of Israel's northern communities to be able to return home safely, and Israel's armed forces should be ready.
The Israeli military said in April it had completed another step in preparing for possible war with Hezbollah that centred on logistics, including preparations for a broad mobilisation of reservists.
More than 250 Hezbollah members and 75 civilians have been killed in Israeli strikes on Lebanon since October, sources in Lebanon say. In Israel, some 20 people - including soldiers and civilians - have been killed.
The fighting between Israel and Hezbollah has marked their worst hostilities since they went to war in 2006.
Hezbollah has repeatedly said that it will cease fire when the Israeli offensive in Gaza stops, but that it is also ready to fight on if Israel continues to attack Lebanon.