Lebanese Shiite militant group Hezbollah today blamed Sunni extremists for killing its top military commander in Syria and vowed to keep fighting to defend President Bashar al-Assad's regime.
The Islamist State (IS) jihadist group, meanwhile, overran a government-controlled hospital in the eastern city of Deir Ezzor, killing 20 members of pro-regime forces and taking medical staff hostage, a monitor said.
Hezbollah has deployed thousands of fighters in Syria where Mustafa Badreddine had led its intervention in support of Assad's forces, which are also backed by Russia and Iran.
Badreddine, who was on a US terror sanctions blacklist and wanted by Israel, was killed in a blast on Thursday night near Damascus international airport.
Hezbollah announced his death yesterday but without immediately apportioning blame, breaking with its usual pattern of accusing arch-foe Israel of responsibility.
Today, it said a probe had concluded that Sunni Islamist radicals known as "takfiris", who consider Shiites to be heretics, had killed Badreddine.
"An investigation has shown that the blast that targeted one of our positions near the Damascus international airport that led to the martyrdom of the brother commander Mustafa Badreddine was caused by artillery bombardment carried out by takfiri groups present in that region," a Hezbollah statement said.
It did not name any specific group, and there has been no claim of responsibility.
Hezbollah has been battling opponents of Assad's regime including Sunni extremists from IS and Al-Nusra Front, Al- Qaeda's Syria affiliate.
A Syrian security source has told AFP that Badreddine was in a warehouse near the airport when it was rocked by a blast on Thursday night.
No aircraft was heard before the explosion, the source said.
The head of the Britain-based Syrian Observatory for Human Rights, Rami Abdel Rahman, said no artillery fire had been heard in the area either in the past three days.
In Deir Ezzor, IS attacked Al-Assad hospital today as it pressed an advance aimed at controlling all of the oil- rich city and its vital airbase, the Observatory said.
The attack sparked clashes with regime forces providing security for the hospital in which six jihadists were killed, the monitor said.
"IS attacked Al-Assad hospital at the city's western entrance, killing at least 20 soldiers and allied fighters," Abdel Rahman said.
