Quneitra, Syria - The Israeli military on Sunday invaded a demilitarized zone in southwest Syria abutting the illegally annexed Golan Heights after Damascus fell to rebel forces.

Israel had already said the day before, as rebels swiftly advanced across Syria, that its soldiers had entered the UN-patrolled buffer zone to "assist" peacekeepers in repelling an attack.

On Sunday, the army announced a troop deployment there, citing "the possible entry of armed individuals into the buffer zone."

"Following the recent events in Syria... the IDF (army) has deployed forces in the buffer zone and in several other places necessary for its defense, to ensure the safety of the communities of the Golan Heights and the citizens of Israel," a military statement said.

Russia Officials confirm Russia is hosting deposed Syrian leader Bashar al-Assad

Israeli forces "will continue to operate as long as necessary in order to preserve the buffer zone and defend Israel," it added.

The Israeli military also claimed it was "not interfering with the internal events in Syria".

A rebel coalition led by Salafist group Hayat Tahrir al-Sham entered Damascus Sunday, putting an end to 24 years of rule by President Bashar al-Assad, who fled the country.

Rami Abdel Rahman, head of the Syrian Observatory for Human Rights, said on Saturday that Syrian army forces had withdrawn from positions in Quneitra province, which includes part of the Golan Heights.

Most of the plateau has been illegally occupied since 1967 by Israel, which annexed it in a move not recognized by most of the international community.

The buffer zone was established in 1974 after Israel and Syria struck a disengagement agreement, with UN peacekeepers stationed there since.

World Haiti's voodoo community targeted in horrific massacre: "Direct attack on humanity"

But Israeli Prime Minister Benjamin Netanyahu declared the agreement null and void, ordering his military to "seize the buffer zone and the commanding positions nearby."

Israel also has troops on Lebanese territory, despite a fragile truce with the militant group Hezbollah, and is carrying out a genocidal assault on Palestinians in Gaza, for which Netanyahu is subject to an arrest warrant issued by the International Criminal Court.