By Ari Rabinovitch and Maya Gebeily

JERUSALEM/BEIRUT (Reuters) -The Israeli military said on Saturday it had killed Hezbollah leader Sayyed Hassan Nasrallah in an airstrike on the group's central headquarters in the southern suburbs of Beirut a day earlier.

Reuters could not immediately reach Hezbollah officials for comment on the Israeli army statement. The Iran-backed Hezbollah has yet to issue any statement on the status of Nasrallah, who has led the group for 32 years.

During Nasrallah's decades in charge, Hezbollah has grown into a regional force that has projected Tehran's influence across the Middle East.

His death would not only mark an enormous blow to Hezbollah, but also to Iran, whose Revolutionary Guards founded the group in 1982. The Israeli military "eliminated ... Hassan Nasrallah, leader of the Hezbollah terrorist organization," Israeli army spokesperson Avichay Adraee wrote in a statement on X.

Another top Hezbollah leader - Ali Karaki - was also killed, he added.

"Hassan Nasrallah will no longer be able to terrorize the world," the Israeli military said in a separate post.

Friday's attack on Hezbollah's command centre, followed by further airstrikes on Saturday, have escalated the conflict between Israel and the heavily armed group, adding to concerns the region could be sucked into a broader war.

Adraee's statement, posted in Arabic, said Israel had struck Hezbollah's underground headquarters while its leadership were "coordinating terrorist activities against the citizens of Israel".

Late on Friday, a source close to Hezbollah told Reuters that Nasrallah was not reachable.

In the first hours after Friday's strike, a source close to Hezbollah told Reuters that Nasrallah was alive. Iran's Tasnim news agency also reported he was safe. A senior Iranian security official told Reuters that Tehran was checking his status.

Israel followed up on Friday's attack with a new wave of airstrikes on Beirut's southern suburbs and other areas of Lebanon on Saturday.

(Reporting by Maya Gebeily, Timour Azhari, Laila Bassam in Beirut; James Mackenzie and Ari Rabinovitch in Jerusalem, Jana Choukeir, Nadine Awadalla, Adam Makary, Jaidaa Taha in Dubai, Writing by Tom Perry, Editing by Frances Kerry and Angus MacSwan)