Israel launches strikes on Hezbollah in wake of device explosions

Israel launched a series of strikes on Hezbollah targets Thursday as the war against the Lebanon-based group widened in the wake of two consecutive days of explosions triggered in wireless devices.

Israel said it hit at least 30 Hezbollah targets in southern Lebanon, including a weapons storage facility, adding it will continue to "operate against the threat of the Hezbollah."

"The IDF is currently striking Hezbollah targets in Lebanon to degrade Hezbollah's terrorist capabilities and infrastructure," the Israeli army said Thursday afternoon. "The Hezbollah terrorist organization has turned southern Lebanon into a combat zone. For decades, Hezbollah has weaponized civilian homes, dug tunnels beneath them, and used civilians as human shields."

Two large sonic booms shook buildings in Beirut on Thursday as Hezbollah leader Hassan Nasrallah delivered a speech on this week's device explosions. The IDF strikes come as Nasrallah said the use of the devices in civilian areas crossed all laws and red lines.

RELATED: What to know about the 2 waves of deadly explosions that hit Lebanon and Syria

"This criminal act is a major terrorist operation, an act of genocide and massacre and amounts to a declaration of war," Nasrallah said.

"The only way to return the displaced to the north is to stop the aggression on the Gaza Strip and the West Bank. What you are doing will increase the displacement of the displaced from the north and will remove the opportunity for their return," Nasrallah said.

The last two days of explosions in Lebanon, triggered remotely with explosives inside pagers or walkie-talkies, have killed at least 37 people and wounded 2,931, Lebanese Health Minister Firass Al-Abyad said in a press conference Thursday.

Prior to announcing the strikes, Prime Minister Benjamin Netanyahu restated his intention of returning tens of thousands of displaced Israelis to their homes in the north of the country, parts of which have been emptied by the threat of Hezbollah attacks.

Two IDF soldiers were killed by Hezbollah rockets in the north on Thursday, the army said.

RELATED: Israel behind pager explosions, sources say, as Hezbollah vows 'reckoning'

"This is a new phase of the war, it includes opportunities but also significant risks. Hezbollah feels that it is being persecuted and the sequence of military and defense actions will continue," Israel Defense Minister Yoav Gallant said Thursday following the airstrikes.

The Israeli rhetoric was punctuated by the two waves of explosions in Lebanon.

Pager devices exploded on Tuesday prompting chaos in the capital Beirut and across the Hezbollah militant group's southern heartland. On Wednesday, walkie-talkies exploded, some during funeral processions being held for militants killed in Tuesday's explosions.

An ABC News source confirmed that Israel was behind the Tuesday pager attacks. Israeli leaders have not publicly commented on either round of explosions.

RELATED: 9 dead, thousands injured after pagers explode across Lebanon

The Lebanese Health Ministry said 12 people were killed and 2,323 wounded in Tuesday's pager detonations, and another 25 people were killed and 608 wounded in Wednesday's walkie-talkie blasts, according to Al-Abyad.

The Lebanese health minister told reporters that he does not want to comment on security and political matters, but he said "it is certain that what happened in terms of aggression is considered a war crime, as the majority of the injuries were recorded in civilian areas and not in the battlefield, and the government is doing its duty and has called for a meeting of the U.N. Security Council, and human rights organizations are doing their duty on this issue."

Hezbollah said 20 of its members were killed in Wednesday's walkie-talkie explosions. Another 11 were killed in Tuesday's pager explosions in Lebanon and Syria, bringing the overall death toll for the group to 31.

The Iranian-backed group blamed Israel for both waves of explosions and vowed a "reckoning."

The militant group claimed several retaliatory strikes into Israel this week -- including on Thursday morning -- with Israel Defense Forces warplanes and artillery responding.

Cross-border fire has been near-constant since Oct. 8, when Hezbollah began attacks in protest of the Israel Defense Forces operation into the Gaza Strip -- the response to Hamas' Oct. 7 infiltration attack into southern Israel.

But as Gallant told reporters on Wednesday, "I believe that we are at the onset of a new phase in this war."

A source confirmed to ABC News on Wednesday that Israel's 98th Division is being deployed from Gaza battlefields to the north of the country.

"We are determined to change the security reality as soon as possible," Maj. Gen. Ori Gordin, head of the IDF's Northern Command, said. "The commitment of the commanders and the troops here is complete, with peak readiness for any task that will be required."

The war, U.S. officials have long warned, could spiral into a broader conflict involving Iran -- a prime benefactor of both Hezbollah and Hamas.

Notable casualties demonstrated the multinational nature of the crisis. A detonating pager injured at least 14 people in Syria, where both Hezbollah and Iranian forces have been active for several years in support of its President Bashar al-Assad.

Iran's ambassador to Lebanon, Mojtaba Amini, was also among the thousands injured, Iranian officials said. Tehran "will duly follow up on the attack against its ambassador in Lebanon," the country's ambassador to the United Nations said in a letter to U.N. leaders on Wednesday.

Israel and Iran have already exchanged significant strikes since Oct. 7. Israel assassinated a top Islamic Revolutionary Guards Corps commander Mohammad Reza Zahedi in Syria in April and Hamas leader Ismail Haniyeh in Tehran in July. Iran fired a huge barrage of drones and missiles toward Israel in response to Zahedi's killing.

This week's bombings in Lebanon raised the possibility of further action, whether overt or covert. Police announced on Thursday that an Israeli citizen was arrested on suspicion of working with Iranian intelligence to assassinate leaders including Netanyahu and Gallant.

Secretary of State Antony Blinken reiterated U.S. appeals for calm during a press conference in Egypt on Wednesday, where he traveled for fresh Gaza cease-fire talks.

"Broadly speaking, we've been very clear, and we remain very clear about the importance of all parties avoiding any steps that could further escalate the conflict that we're trying to resolve in Gaza," Blinken said.

A conflict spreading to other fronts, he added, is "clearly not in the interest of anyone involved."

The U.S., Blinken and other American officials said, were not involved in or pre-briefed on the remote explosions that rocked Lebanon on Tuesday and Wednesday.

Gallant spoke with Defense Secretary Lloyd Austin three times in two days, the latest conversation on Wednesday reaffirming the "unwavering U.S. support for Israel in the face of threats from Iran, Lebanese Hezbollah, and Iran's other regional partners" and the need for de-escalation, a Pentagon readout said.

U.S. officials were notified by Israeli counterparts on Tuesday that they were planning an operation against Hezbollah, but did not provide any details about what they were going to do, U.S. officials said.

ABC News' Ghazi Balkiz, Will Gretsky, Morgan Winsor, Luis Martinez, Shannon K. Kingston, Ellie Kaufman, Nasser Atta, Jordana Miller and Marcus Moore contributed to this report.