Hundreds of pagers used by Hizbollah members exploded across Lebanon on Tuesday, killing at least nine people and wounding some 2,800 in blasts the group blamed on Israel.
There was no immediate comment from the Israeli military on the wave of explosions, which came just hours after Israel announced it was broadening the aims of the war sparked by Hamas's October 7 attacks to include its fight against Hizbollah along its border with Lebanon.
The sons of Hizbollah lawmakers Ali Ammar and Hassan Fadlallah were among the dead, a source close to the group told AFP, requesting anonymity to discuss sensitive matters.
The blasts "killed nine people, including a girl", Lebanese Health Minister Firass Abiad said in a casualty update.
He added that some "2,800 people were injured, about 200 of them critically" with injuries mostly reported to the face, hands and stomach.
The 10-year-old daughter of a Hizbollah member was killed in east Lebanon's Bekaa Valley when his pager exploded, the family and a source close to the group said.
Tehran's ambassador to Beirut was also wounded in a pager explosion but his injuries were not serious, Iranian state media reported.
In neighbouring Syria, 14 people were wounded "after pagers used by Hizbollah exploded", said a Britain-based war monitor, the Syrian Observatory for Human Rights.
Hizbollah blamed Israel for the blasts and warned it would be punished.
"We hold the Israeli enemy fully responsible for this criminal aggression," the group said in a statement, adding that Israel "will certainly receive its just punishment for this sinful aggression".
The United States, Israel's top arms provider and close ally, was "not involved" and "not aware of this incident in advance", said State Department spokesman Matthew Miller.
The afternoon blasts hit Hizbollah strongholds across Lebanon and dealt a heavy blow to the group, which already had concerns about the security of its communications after losing several key commanders to targeted air strikes in recent months.
Hizbollah had instructed its members to avoid mobile phones after the Gaza war began and to rely instead on the group's own telecommunications system to prevent Israeli breaches.
"Hundreds of Hizbollah members were injured by the simultaneous explosion of their pagers" in the group's strongholds in Beirut's southern suburbs, in south Lebanon and in the eastern Bekaa Valley, a Hizbollah source said, requesting anonymity.
AFP journalists saw dozens of wounded being taken to hospital in Beirut and in the south, where dozens of ambulances rushed between the cities of Tyre and Sidon in both directions.
Education Minister Abbas Halabi announced the closure of schools and universities on Wednesday "in condemnation of the criminal act committed by the Israeli enemy".
Earlier Tuesday, Israel announced it was broadening the aims of the war sparked by the Hamas attacks to include its fight against Hizbollah along its border with Lebanon.
To date, Israel's objectives have been to crush Hamas and bring home the hostages seized by Palestinian group during the October 7 attacks that sparked the war.
"The political-security cabinet updated the goals of the war this evening, so that they include the following section: the safe return of the residents of the north to their homes," Israeli Prime Minister Benjamin Netanyahu's office said in a statement.
Since October, the unabating exchanges of fire between Israeli troops and Hamas ally Hizbollah in Lebanon have forced tens of thousands of people on both sides of the border to flee their homes.
Not formally declared as a war by Israel, the exchanges of fire between Israeli troops and Hizbollah have killed hundreds of mostly fighters in Lebanon, and dozens on the Israeli side.
On Monday, Israeli Defence Minister Yoav Gallant warned that failing a political solution, "military action" would be "the only way left to ensure the return of Israel's northern communities".
Before the wave of pager explosions, Israel said it killed three Hizbollah members in a strike on Lebanon on Tuesday.
"The possibility for an agreement is running out as Hizbollah continues to tie itself to Hamas," Gallant's office quoted him as telling visiting US envoy Amos Hochstein.
Netanyahu later told Hochstein he was seeking a "fundamental change" in the security situation on Israel's northern border.
Hizbollah deputy chief Naim Qassem said at the weekend that his group had "no intention of going to war", but that "there will be large losses on both sides" in the event of all-out conflict.
US Secretary of State Antony Blinken was due back in the region to try to revive stalled ceasefire talks for the Israel-Hamas war in Gaza.
After months of mediated negotiations failed to pin down a ceasefire, Washington said it was still pushing all sides to finalise an agreement.
US officials have expressed increasing frustration with Israel as Netanyahu has publicly rejected US assessments that a deal is nearly complete and has insisted on an Israeli military presence on the Egypt-Gaza border.
The October 7 attack on southern Israel that sparked the war resulted in the deaths of 1,205 people, mostly civilians, according to an AFP tally based on official Israeli figures.
Israel's retaliatory military offensive has killed at least 41,252 people in Gaza, according to health ministry.
On Tuesday, UN member states were debating a draft resolution demanding an end to the Israeli occupation of all Palestinian territories within 12 months.
General Assembly resolutions are not binding, but Israel has already denounced the new text as "disgraceful".
In Gaza, rescuers said several Israeli air strikes killed at least seven people overnight.
Agence France-Presse