Israel launched strikes against Lebanon's Hezbollah just hours after the group's leader vowed retaliation for Israel's deadly explosions that destroyed its communication devices, resulting in 37 deaths and thousands of injuries.

The Iran-backed Hezbollah accused Israel of being responsible for the destruction of thousands of its operatives' pagers and radios in a series of attacks over two days this week. Israel has not yet responded to these allegations.

In his first comments since the deadly sabotage, Hezbollah leader Hassan Nasrallah declared Thursday that Israel would face consequences.

Describing the attacks as a "massacre" and a possible "act of war," Nasrallah said Israel would face "just punishment, where it expects it and where it does not."

As he delivered his address, Israeli fighter jets roared over Beirut, their sonic booms shaking buildings and sending residents scrambling for cover.

Hours later, Israel's military said its jets hit "approximately 100 launchers and additional infrastructure sites, consisting of approximately 1,000 barrels" set to be fired immediately.

Lebanon's state-run National News Agency reported that Israel struck southern Lebanon at least 52 times, marking one of the heaviest bombardments since the border exchanges erupted last October.

Hezbollah, meanwhile, said it launched at least 17 attacks on military sites in northern Israel.

The device blasts and Thursday's barrage of airstrikes came after Israel announced it was shifting its war objectives to its northern border with Lebanon, where it has been trading fire with Hezbollah.

For nearly a year, Israel's genocidal firepower has focused on the Palestinian resistance group Hamas in Gaza killing over 41,000 people, motly women and children, but its troops have also been engaged in near-daily exchanges with Hezbollah.

International mediators have repeatedly tried to avert a full-blown war between Israel and Hezbollah and to mitigate the regional fallout from the latest flareup of the conflict in Gaza, which began Oct. 7.

Hezbollah says its fight is in support of Hamas, and Nasrallah vowed the attacks on Israel would continue as long as Israel's genocidal war in Gaza continues.

The cross-border exchanges of fire have killed hundreds in Lebanon and dozens in Israel.

Tens of thousands of people on both sides of the border have been forced to flee their homes.

Speaking to Israeli troops on Wednesday, Israeli Defense Minister Yoav Gallant said, "Hezbollah will pay an increasing price" as Israel tries to "ensure the safe return" of its citizens to areas near the border.

"We are at the start of a new phase in the war," he said.

Wider war

Lebanese Foreign Minister Abdallah Bou Habib said the "blatant assault on Lebanon's sovereignty and security" was a dangerous development that could "signal a wider war."

Speaking ahead of a U.N. Security Council meeting on the attacks set for Friday, he said Lebanon had filed a complaint against "Israel's cyber-terrorist aggression that amounts to a war crime."

Iran's Revolutionary Guards said Israel faces "a crushing response from the resistance front" after the blasts, which wounded Tehran's ambassador in Beirut.

U.S. Secretary of State Antony Blinken, who has been scrambling to salvage efforts for a Gaza cease-fire and hostage release deal, called for restraint from all sides.

"We don't want to see any escalatory actions by any party" that would endanger the goal of a cease-fire in Gaza, he said as he joined European foreign ministers in Paris to discuss the widening crisis.

U.S. Press Secretary Karine Jean-Pierre said President Joe Biden still believes a diplomatic solution between Israel and Hezbollah is "achievable."

Palestinian President Mahmud Abbas, in Madrid, called for a new peace conference aimed at ending the Israeli-Palestinian conflict.

Hamas's Oct. 7 attacks that sparked the latest round of conflict in Gaza resulted in the deaths of 1,205 people. Out of 251 hostages seized by Hamas, 97 are still held in Gaza.

Israel's retaliatory genocidal offensive has killed at least 41,272 people in Gaza, most of them civilians. The United Nations has acknowledged these figures as reliable.

In the latest violence in Gaza, the territory's civil defense agency said an Israeli airstrike on a house in Nuseirat refugee camp killed eight people.

Another six people, including children, were killed in a separate strike on an apartment in Gaza City, it added.

In Lebanon, the influx of casualties following the blasts overwhelmed medics and triggered panic.

"What happened in the last two days is so frightening. It's terrifying," Lina Ismail told Agence France-Presse (AFP) by phone from the eastern city of Baalbek.

"I took away my daughter's power bank, and we even sleep with our mobile phones in a separate room," she added in a trembling voice.

Sabotaged at source

The preliminary findings of a Lebanese investigation found the pagers had been booby-trapped, a security official said.

The country's mission to the United Nations concurred, saying in a letter that the probe showed "the targeted devices were professionally booby-trapped ... before arriving in Lebanon, and were detonated by sending emails to the devices."

A source close to Hezbollah, who asked not to be identified, said the pagers were recently imported and appeared to have been "sabotaged at source."

The New York Times reported Wednesday that the pagers that exploded were produced by the Hungary-based BAC Consulting on behalf of Taiwanese manufacturer Gold Apollo. It cited intelligence officers as saying BAC was part of an Israeli front.

A government spokesperson in Budapest said the company was "a trading intermediary, with no manufacturing or operational site in Hungary."