The cross-border attacks occurred as high-level talks resumed in Egypt, aiming for a cease-fire between Israel and Hamas in the war in Gaza to ease regional tensions.

Hezbollah claimed to have hit an Israeli military intelligence site near Tel Aviv with hundreds of rockets and drones. In contrast, Israel claimed its strikes were preemptive to prevent a more significant attack, but neither side provided evidence.

Hezbollah leader Hassan Nasrallah said the attack was in response to Israel’s killing of a top militant commander in Beirut last month, which had been delayed to give the Gaza cease-fire talks a chance and to allow Iran-backed groups to discuss with Iran whether to attack Israel simultaneously. Israeli and U.S. military deployments also played a role.

“We reserve the right to respond at a later time” if the results of Sunday’s attack aren’t sufficient, Nasrallah said, adding that allied Houthi rebels in Yemen and Iran itself had yet to respond. However, he assured the Lebanese people to “take a breath and relax.”

Israel’s military said its intelligence base near Tel Aviv wasn’t hit.

Both Israel and Hezbollah claimed to have aimed only at military targets. Israel’s military reported one navy soldier killed and two others wounded by incoming fire or shrapnel. Two Hezbollah fighters and a militant from an allied group were killed.

Israeli Prime Minister Benjamin Netanyahu said the military had destroyed thousands of rockets aimed at northern Israel and thwarted drones heading for the country center.

He also warned, “This is not the end of the story.”

Air raid sirens were reported throughout northern Israel, and the international airport closed and diverted flights for about an hour. Israel’s Home Front Command later lifted restrictions in most areas.

An Israeli military spokesman, Lt. Col. Nadav Shoshani, said Hezbollah intended to hit targets in northern and central Israel, but initial assessments found “very little damage.” He said around 100 Israeli aircraft took part in the strikes.

Hezbollah said its attack involved more than 320 Katyusha rockets aimed at multiple sites in Israel and a “large number” of drones.

Some Israelis were shaken. In the northern city of Acre, retired teacher Saadia Even Tsur, 76, said he was at the synagogue when his bedroom was damaged and arrived home five minutes later. “I went up and saw the size of the miracle that happened to me,” he said. A window was broken, and debris was on his bed.

After an emergency government meeting, Lebanon’s caretaker Economy Minister Amin Salam said officials were “feeling a bit more optimistic” about de-escalation. “We feel more reassured since both sides confirmed that the expected operations ended,” he said.

President Joe Biden was “closely monitoring events in Israel and Lebanon,” according to Sean Savett, a spokesman for the National Security Council. The Pentagon said Defense Secretary Lloyd Austin spoke with his Israeli counterpart, Yoav Gallant. The chairman of the Joint Chiefs of Staff, Gen. CQ Brown, arrived in Israel late Sunday for meetings on what the Israeli military called “joint preparations in the region as part of the response to threats in the Middle East.”

Danny Citrinowicz, an expert at Israel’s Institute for National Security Studies, said Hezbollah might be trying to “balance the equation without escalating into war.” He said each side hopes its narrative will be sufficient to declare victory and avoid a wider confrontation.

Hezbollah began attacking Israel almost immediately after the start of the war in Gaza, which was triggered by Hamas’ Oct. 7 attack on southern Israel. Israel and Hezbollah have exchanged fire almost daily, displacing tens of thousands of people on both sides of the border.

Hezbollah, which fought Israel to a stalemate in 2006, is believed to be far more powerful now, with the United States and Israel estimating it has some 150,000 rockets and is capable of hitting anywhere inside Israel. The group has also developed drones capable of evading Israel’s defenses, as well as precision-guided munitions.

Israel has vowed a crushing response to any major Hezbollah attack. It has an extensive multi-tiered missile defense system, and it is backed by a U.S.-led coalition that helped it shoot down hundreds of missiles and drones fired from Iran earlier this year. The U.S. military has been building up its forces across the region in recent weeks.

Hezbollah is a close ally of Iran, which has also threatened to retaliate against Israel for the killing of a senior Hamas leader, Ismail Haniyeh, in Tehran last month. Iran has not confirmed its involvement in the recent attacks.