A senior Hezbollah commander has been killed in Syria, the Lebanon-based Shia militant organisation says.
Mustafa Amine Badreddine died in a large explosion near Damascus airport, Hezbollah said in a statement on the website of its al-Manar network.
It rolled back on an earlier claim that Israel was responsible.
Badreddine is accused, with three other alleged Hezbollah members, of assassinating former Lebanese PM Rafik Hariri in Beirut in 2005.
Lebanon’s al-Mayadeen TV had earlier said that Badreddine died in an Israeli air strike. Israel has not commented on the claim.
Announcing Badreddine’s death, Hezbollah said in an initial statement: “He took part in most of the operations of the Islamic resistance since 1982.”
The second statement, on al-Manar’s website, said: “The investigation will work on determining the nature of the explosion and its causes and whether it was a result of an air, missile or artillery attack.
“We will announce further results of the investigations soon.”
Born in 1961, he is believed to have been a senior figure in Hezbollah’s military wing.
He was a cousin and brother-in-law of Imad Mughniyeh, who was the military wing’s chief until his assassination by car bomb in Damascus in 2008.
Badreddine is reported to have sat on Hezbollah’s Shura Council and served as an adviser to the group’s overall leader Hassan Nasrallah.
According to one report, a Hezbollah member interrogated by the Canadian Security Intelligence Service (CSIS), described Badreddine as “more dangerous” than Mughniyeh, who was “his teacher in terrorism”.
They are alleged to have worked together on the October 1983 bombing of the US Marine Corps barracks in Beirut that killed 241 personnel.
He was on a US sanctions list.
Hezbollah, the Party of God, is a Shia Islamist political, military and social organisation that wields considerable power in Lebanon.
It emerged with the help of Iran during the Israeli occupation of Lebanon in the early 1980s, though its ideological roots stretch back to the Shia Islamic revival in Lebanon in the 1960s and ’70s.