Israel killed Hezbollah leader Sayyed Hassan Nasrallah in a powerful airstrike in Beirut, dealing a heavy blow to the Iran-backed group as it reels from an escalating campaign of Israeli attacks.

The Israeli military said on Saturday it had eliminated Nasrallah in the strike on the group's central command headquarters in Beirut's southern suburbs on Friday. Hezbollah confirmed he had been killed, without saying how.

Nasrallah's death is a major blow to both Hezbollah and Iran, removing an influential ally who helped build Hezbollah into the linchpin of Tehran's network of allied groups in the Arab world.

Israeli Prime Minister Benjamin Netanyahu described Nasrallah's killing as a necessary step toward "changing the balance of power in the region for years to come."

"Nasrallah was not a terrorist, he was the terrorist," Netanyahu said in a statement, warning of challenging days ahead.

President Joe Biden described Nasrallah's death as a measure of justice for what he called his many victims, including thousands of Americans, Israelis, and Lebanese, and said the U.S. fully supported Israel's right to self-defense.

A senior member of Iran's Revolutionary Guard, deputy commander Abbas Nilforoushan, was also killed in the Israeli attacks in Beirut on Friday, Iranian media reported.

Sources told Reuters that Iranian Supreme Leader Ayatollah Ali Khamenei had been moved to a secure location in Iran following Nasrallah's killing.

Strikes continued on Beirut's southern suburbs throughout the early evening on Saturday, according to a Reuters live broadcast, sending large clouds of smoke over the city.

One Israeli strike hit an industrial area just over 500 yards from Beirut airport buildings, a security source told Reuters. The airport continued to operate normally, according to Middle East Airlines boss Mohammad al-Hout.

More than 1,000 people have been killed and more than 6,000 wounded as a result of Israeli attacks in the past two weeks, the health ministry said, and about 1 million Lebanese have been displaced by the strikes, including hundreds of thousands since Friday, Nasser Yassin, the minister coordinating the government's crisis response, told Reuters on Saturday.

Israel said it killed a senior Hezbollah intelligence official in a strike on southern Beirut, naming him as Hassan Khalil Yassin. Hezbollah has made no mention of this.

In Israel, air raid sirens sounded across the center of the country — including Tel Aviv — and large bangs were heard after a missile was fired from Yemen and intercepted, according to the Israeli military.

Hezbollah said in a statement that it would continue its battle against Israel "in support of Gaza and Palestine, and in defense of Lebanon and its steadfast and honorable people."

Iran's Khamenei said Nasrallah's death would be avenged and his path in fighting Israel would be pursued by other militants.

Lebanon's caretaker Prime Minister Najib Mikati said his country was facing the threat of danger, without mentioning the death of Nasrallah. His office later announced three days of mourning for the Hezbollah chief.

Hezbollah and Israel have been fighting a conflict in parallel with Israel's war against the Palestinian group Hamas in Gaza since Hamas' attack on Israel last Oct. 7, in a cross-border confrontation that has sharply escalated in recent days.

Hezbollah's Al-Manar TV aired verses from the Koran after Nasrallah's death was announced. Bursts of gunfire were heard in Beirut and Lebanon's army deployed tanks in the city center, according to Reuters witnesses.

The Israeli military said Nasrallah was eliminated in a "targeted strike" on the group's underground headquarters below a residential building in Dahiyeh — a Hezbollah-controlled southern suburb of Beirut. It said he was killed along with senior Hezbollah official Ali Karaki and other commanders.

Nasrallah's death is by far the largest blow in a traumatic fortnight for Hezbollah, starting with a deadly strike on thousands of communications devices used by its members.

Days later, Israel significantly ramped up airstrikes in Lebanon, killing several top Hezbollah commanders and hundreds of other people across wide areas of the country.

Succession

Many Hezbollah supporters were in disbelief on Saturday.

"He was leading us. He was everything to us. We were under his wings," one supporter, Zahraa, told Reuters tearfully by phone from a school where she had been displaced to overnight.

Hezbollah gave no immediate indication of who might succeed Nasrallah. Senior Hezbollah official Hashem Safieddine has long been regarded as heir apparent. The group has not issued any statement on Safieddine's status or that of any other Hezbollah leaders — apart from Nasrallah — since the attack.

Hezbollah continued its cross-border rocket fire on Saturday, setting off sirens and sending residents running for shelter deep inside Israel. Israeli missile defenses blocked some of them and there was no immediate report of injuries.

The escalation has increased fears the conflict could spin out of control, potentially drawing in Iran, Hezbollah's principal backer, as well as the United States.

Israeli Defense Minister Yoav Gallant said Israel's war was not with the Lebanese people, calling Nasrallah the "murderer of thousands of Israelis and foreign citizens." Gallant held talks late on Saturday about possibly expanding Israel's military offensive on its northern front, his office said.

Biden, who had no advance warning of the strike that killed Nasrallah, said the U.S. aimed to de-escalate the conflicts in Gaza and Lebanon through diplomatic means.

Hezbollah has said it would cease fire only when Israel's Gaza offensive ends. Hamas and other allies of Hezbollah issued statements mourning his death.

Russia said it strongly condemned Nasrallah's killing and urged Israel to stop hostilities in Lebanon.

Lebanon Asks Iranian Plane Not to Land

Residents fled Dahiyeh, seeking shelter in downtown Beirut and other parts of the city.

"Yesterday's strikes were unbelievable. We had fled before and then went back to our homes, but then the bombing got more and more intense, so we came here, waiting for Netanyahu to stop the bombing," said Dalal Daher, speaking near Beirut's Martyrs Square.

Israel says it has been attacking Hezbollah with the aim of allowing tens of thousands of residents evacuated from northern Israel to return home.

Lebanon's transport ministry asked an Iranian plane not to enter Lebanese airspace after Israel warned air traffic control at the Beirut airport that it would use "force" if it landed, a ministry source told Reuters. The source said it was not clear what was on the plane, adding: "The priority is people."

Late on Friday, Israeli military spokesperson Rear Admiral Daniel Hagari said Israeli air force planes were "patrolling the area of the Beirut airport" and would not allow "hostile flights with weapons to land" there.

Iran Air has canceled all flights to Beirut until further notice, the airline's spokesman told local media on Saturday.