JERUSALEM — Israel has concluded that Hezbollah’s top military commander was killed in Syria last year by rivals within the Shi’ite militant group, Israel’s military chief said Tuesday.
The explosive report was the latest sign of an escalating feud between Israel and Hezbollah, an Iranian-backed group sworn to Israel’s destruction.
Israel considers Hezbollah to be a potent enemy, with over 100,000 rockets and missiles aimed at the Jewish state. But it also believes the group has been weakened and demoralized after years of fighting alongside President Bashar Assad’s forces in Syria.
Israel’s military chief, lieutenant General Gadi Eisenkot, told an academic conference on Tuesday that the death of Mustafa Badreddine last May illustrated ‘‘the depth of the internal crisis within Hezbollah.’’
He also said it reflected ‘‘the extent of the cruelty, complexity and tension between Hezbollah and its patron Iran.’’
An Israeli military official said Israel believes the order to kill Badreddine was given by Hezbollah’s leader, Hassan Nasrallah.
Israeli intelligence believes Badreddine had been feuding with Iranian military commanders in Syria over the heavy losses his group had suffered on the battlefield. Both Iran and Hezbollah are backing Syrian government forces. The official spoke on condition of anonymity because he was discussing a confidential intelligence assessment.
Hezbollah had no immediate comment.
At the time of his death last year, Hezbollah said Badreddine had been killed by insurgent shelling in Syria. He was considered Hezbollah’s top military official and was among five members on trial in absentia at a court in the Netherlands over the bombing that killed former Lebanese Prime Minister Rafik Hariri and 21 others in Beirut in 2005.
Badreddine was a student of Imad Mughniyeh, Hezbollah’s previous military chief, who was considered one of the world’s most-wanted terrorists by Israel and the United States.
Mughniyeh, who was Badreddine’s brother-in-law, was killed in a 2008 car bombing in Damascus that Hezbollah blamed on Israel.
Israel and Hezbollah fought a monthlong war in 2006 that ended in a stalemate. Israeli officials say Hezbollah is far stronger than it was back then and battle tested because of its involvement in the Syrian war.
But Israeli officials also say the group does not want a confrontation with Israel right now. Hezbollah has gotten bogged down in the Syrian fighting and is believed to have lost hundreds of fighters.
In a separate development Tuesday, Israel’s Shin Bet security agency said it had arrested a Palestinian employee of a humanitarian program run by the Turkish government on suspicion of diverting funds to militants.
The Shin Bet said its interrogation of Muhammad Murtaja, the coordinator of the Gaza branch of the Turkish Cooperation and Coordination Agency, revealed how he had duped the organization by shifting funds to the military wing of the Islamic militant group Hamas, which rules Gaza.
It said Murtaja’s activities included military training, manufacturing weapons, and digging tunnels into Israel.
