Austrian troops in the UN monitoring force on the Golan Heights began withdrawing on Wednesday, days after Vienna decided to quit the mission over security concerns linked to Syria's civil war, AFP reported.
A group of about 70 soldiers entered the Israeli side of the strategic plateau through the Quneitra crossing, the only direct passage between Israel and Syria.
The troops, the first wave of the 378-strong Austrian contingent which is due to be pulled out in stages, arrived in jeeps accompanied by armored vehicles before crossing through Syrian and Israeli controls.
As they passed through security checks, the peacekeepers said they were always aware that the situation could flare up at any time.
"Well, of course we were in a war zone, we knew that," one of them, Erwin Klem, told an AFP correspondent.
"And we protected ourselves accordingly, using bullet-proof vehicles and protective equipment, too."
They briefly entered a UN base on the Israeli side of the line, but shortly afterwards set out for Ben Gurion international airport near Tel Aviv in a convoy of five coaches accompanied by six smaller vehicles.
Austria, which has been a cornerstone of UNDOF, the UN force monitoring a ceasefire between Syria and Israel since 1974, announced on Thursday it would withdraw its peacekeepers because of deteriorating security.
Defence Minister Gerald Klug said the pullout would take two to four weeks.
A top Israeli government official told AFP on Tuesday that several dozen Austrian troops had already left the mission's headquarters. Israeli public radio said they were administrative staff.
"But the majority of soldiers will remain in place until the UN has found a country that can send troops to replace the Austrian ones," said the Israeli official, who asked not to be named.
The United Nations is trying to persuade Austria to slow down its withdrawal from the force which, since March, has numbered just over 900 troops.
When completed, the Austrian pullout will leave the force with just 534 troops: 341 from the Philippines and 193 from India, UN officials say.
A year ago UNDOF had more than 1,100 troops. But Japan and Croatia have pulled out their men in recent months as battles between Syrian troops and the rebels spilled into the ceasefire zone.
Earlier this year, Israel expressed concern the UN force might pull out altogether after rebels snatched 21 peacekeepers from the demilitarized zone.
Israel fears the departure of UNDOF troops could leave a vacuum in the ceasefire zone, leaving it open to infiltration by hardline militant groups like Al-Qaeda.
But it has vowed not to rely on international forces to ensure its own security.
"The disintegration of the UN force in the Golan clarifies the fact that Israel cannot base its security on international forces," Prime Minister Netanyahu said this week.
"They can be part of the arrangements, but not the main foundation for Israel's security," the Israeli leader said.
Moscow has offered to send Russian troops to bolster the depleted UNDOF.
But under the terms of the 1974 agreement which established the peacekeeping force, no troops from the permanent five members of the UN Security Council can participate.