Hezbollah has mourned its top commander Fouad Shukur, whose body was recovered from the rubble of an Israeli strike in south Beirut, as fears mounted of a wider conflict.

Shukur will be buried on Thursday and Hezbollah leader Sayyed Hassan Nasrallah will speak at his funeral to outline the Iran-backed movement's position, the group said in a statement.

Two back-to-back strikes in Beirut and Tehran, both attributed to Israel and targeting high-ranking figures in Hamas and Hezbollah, have left Hezbollah and Iran in a quandary.

Analysts agree that both strikes hit too close to home to pass without a response, and were serious security breaches for Iran and Hezbollah. Calibrating that response to restore deterrence without sparking an even more damaging escalation may be the most delicate balancing act in nearly a year of teetering on the brink of a regional war.

Israeli Foreign Minister Israel Katz has sent a letter to dozens of foreign ministers, calling on them to demand “an immediate cessation of Hezbollah’s attacks, its withdrawal to north of the Litani River, and its disarmament in accordance with U.N. Security Council Resolution 1701.”

“Israel is not interested in an all-out war,” he continues, “but the only way to prevent it is the immediate implementation of Resolution 1701.”

Caretaker Prime Minister Najib Mikati on Wednesday described Israel’s deadly strike on Haret Hreik as “a strike on initiatives, pacification efforts and understandings.”

“We will continue to work to rescue our country and protect our society from any danger,” Mikati added, during an emergency cabinet session tackling the strike on Beirut’s southern suburbs and its repercussions.

U.S. Defense Secretary Lloyd Austin has spoken with Israeli Defense Minister Yoav Gallant regarding the “threat” posed by Hezbollah, the Pentagon said, hours after Israel said it killed Hezbollah’s most senior military commander Fouad Shukur in a rare strike on Beirut’s southern suburbs.

“They discussed the threats to Israel posed by a range of Iranian-backed terrorist groups, including Lebanese Hezbollah,” the readout said without referring to the strike on Shukur and the killing of Hamas leader Ismail Haniyeh in Tehran, an operation also blamed on Israel.

Anger simmered after Israel struck a southern Beirut suburb that is also a Hezbollah stronghold, with young men chanting in support of the group at the site of the strike.

Israel hit Hezbollah's stronghold in retaliation for rocket fire from Lebanon that killed 12 children over the weekend in the occupied Golan Heights, saying it had targeted the commander responsible for the attack.

Hezbollah condemned Israel's killing of Hamas leader Ismail Haniyeh on Wednesday, warning his death will only increase the resolve of Iran-backed "resistance" groups.

Hamas said Haniyeh was killed in an Israeli strike in the Iranian capital, where he was attending the swearing-in of the country's new president, and vowed the act "will not go unanswered".

The Hezbollah commander who the Israeli military says it killed in an airstrike Tuesday had been blamed by Israel for a deadly weekend rocket attack and was accused by the U.S. of orchestrating the 1983 bombing in Beirut that killed 241 American servicemen.

A statement from Israeli military spokesperson Daniel Hagari said the target of the strike, Fouad Shukur, was behind the Saturday rocket attack on the town of Majdal Shams that killed 12 young people in the Israeli-occupied Golan Heights of Syria.

Hezbollah said Wednesday they were still searching for the body of a top commander targeted in an Israeli strike in Beirut.

The group’s first comment after the strike targeting Fouad Shukur came hours after his death Tuesday and followed the overnight strike in Tehran that killed Haniyeh.

The Israeli military said late Tuesday that it wanted to avoid any wider war with Hezbollah but that its forces were ready for "any scenario."

"Hezbollah's ongoing aggression and brutal attacks are dragging the people of Lebanon and the entire Middle East into a wider escalation," military spokesman Rear Admiral Daniel Hagari said in a statement.