The fate of a senior Hezbollah commander remains unknown following an Israeli strike against him in southern Beirut.

The Lebanese group said early Wednesday that Fuad Shukr had been in the building targeted by the strike, without providing further detail.

Israel's military announced late Tuesday it had killed Shukr, whom it named as Hezbollah's most senior commander and whom it blamed for a weekend attack that killed 12 youngsters in the Israeli-occupied Golan Heights.

Iran-backed Hezbollah has denied any involvement in Saturday's attack.

Israeli Defence Minister Yoav Gallant claimed Shukr "has the blood of many Israelis on his hands. Tonight, we have shown that the blood of our people has a price and that there is no place out of reach for our forces to this end."

A senior security source from another country in the region confirmed Shukr had died of his wounds. At least two women and two children were also killed, medical and security sources said.

Hezbollah's long-awaited statement Wednesday said Israel had attacked a residential building in the southern suburbs of Beirut, a stronghold for the group, and that "a number of citizens" had been killed and others wounded.

It said Shukr "was present in this building at the time" but that the group was still awaiting definitive results on his fate.

Shukr was an adviser to Hezbollah leader Sayyed Hassan Nasrallah, according to Hezbollah sources and the Israeli military's announcement of his killing.

His apparent killing marks the most senior Hezbollah commander to have been killed in nearly 10 months of exchanges of fire between the Israeli military and Hezbollah, taking place in parallel with Tel Aviv's genocidal war on Gaza War.

The strike on Beirut came shortly before the assassination of Hamas leader Ismail Haniyeh in the early hours of Wednesday in Iran, in a development that has further fanned fears of wider regional escalation. Hezbollah is an ally of Hamas.

'We are up for it'

On Wednesday morning, Lebanon's civil defense teams were on the ground in the southern suburbs of Beirut, known as Dahiyeh, clearing rubble from the strike, according to a Reuters witness.

The attack appeared to have shorn off the top corner of a multi-storey building and scattered bits of charred debris onto the surrounding buildings and streets.

Lebanese ministers and lawmakers visited the scene Wednesday. Speaking from the ruins, Hezbollah parliamentarian Ali Ammar condemned the strike on Dahiyeh as well as the killing of Haniyeh in Tehran. Israel has made no comment on Haniyeh's assassination.

"This enemy (Israel) demands war and we are up for it, God willing, we are up for it," Ammar said.

Lebanon's cabinet held an emergency meeting on Wednesday morning to discuss the strike on Beirut and issued a statement read to reporters by Information Minister Ziad Makary.

Makary condemned the strike and said retaliation by Hezbollah was anticipated but that the government was worried the situation could "spiral."

"Lebanon does not want war," he said, adding that the government would engage in diplomatic efforts to calm tensions.