After a heavy exchange of fire early Sunday between Israel and Iran-backed Shiite militia Hezbollah, the regional military powers signaled a desire to avoid a spiral that could lead to a wider Mideast conflict. Hezbollah launched hundreds of rockets and drones at Israel as around 100 Israeli warplanes struck targets in Lebanon in a move Israel said was intended to pre-empt a Hezbollah attack. The exchange was a significant show of force but initially appeared to result in few casualties and limited damage. Hezbollah said Sunday its operation for the day had concluded. “We said this was a preliminary response,” Hezbollah leader Hassan Nasrallah said in an address Sunday. “If we assess that the impact of the preliminary response was not satisfactory, we will act accordingly. For now we consider that the response is over, and the country can take a breath.” The Middle East has been on edge for weeks, waiting to see how Hezbollah and its patron Iran would respond to a pair of Israel-linked killings of senior figures from Hezbollah and Palestinian Islamist militant group Hamas in Beirut and Tehran. Hamas, the Yemen-based Houthis and other Iran-backed militias congratulated Hezbollah on the operation. Iran, which had vowed to retaliate for the killing in Tehran, has remained largely silent. Israel said after the attacks that its military was back in a defensive posture, though it continued to strike some targets in southern Lebanon as it has for the past 10 months.

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