The official television station of the Lebanese resistance movement Hezbollah said on Wednesday that "two members of Syria's National Defense Forces (a branch of Syrian Armed Forces) were killed when an Israeli drone targeted their car at the entrance of Hader, in Quneitra Province".
However, the so-called Syrian Observatory for Human Rights said five people in total were killed in the airstrike.
The UK-based group said an Israeli plane had hit a car, killing two men from the Lebanese resistance movement Hezbollah, and three men from pro-government popular committees in the Druze town, Press TV reported.
The Israeli military has not yet commented on the attack.
Hader borders the line separating Syria’s side of the Golan Heights from the Israeli section, occupied since the war of 1967.
The Druze town has been witnessing clashes between militants and members of pro-Syrian government groups in recent weeks.
The attack in Syria on Wednesday is not the first to be carried out by Israel.
Back in January, an Israeli attack claimed the lives of six Hezbollah fighters near Quneitra.
The Tel Aviv regime has carried out at least five airstrikes against the region over the past year.
Along with Syrian forces, Hezbollah fighters are fighting ISIL and other foreign-backed militant groups, which have been operating in Syria against the government of Syrian President Bashar al-Assad since March 2011.