QUNEITRA, Golan Heights — Syrian rebels briefly seized control of a border crossing along the Israeli-controlled Golan Heights on Thursday, prompting the withdrawal of a major Austrian peacekeeping contingent and heightening fears in Israel that it could soon be dragged into the neighboring country's civil war.
From the Israeli side of the Golan, Syrian tanks and armored vehicles could be seen across the border. Large explosions could be heard throughout the day, and thick smoke and flames rose from the area. Israeli TV stations showed images of Israeli tourists flocking to the Golan to look across the frontier and gawk at the fighting.
Israeli troops along the border were on high alert, although the military said no special actions had been taken in response to the escalation.
By nightfall, the situation appeared to be quieting down. Israel's deputy defense minister, Danny Danon, said forces remained on high alert, but no special actions had been taken.
"We are following very carefully what's happening in Syria," Danon told The Associated Press. "We will do whatever is necessary to protect the interests of Israel."
Israel fears that Islamic militants who have joined the rebel ranks in trying to oust President Bashar Assad will turn their guns toward Israel if they topple the Syrian leader. Islamic groups are believed to be active in the fighting in the Golan area. Israel has also expressed concerns that Assad's sophisticated weapons, could slip into the hands of hostile groups, including Assad's ally, Hezbollah.
The Jewish state has kept a wary eye on the fighting next door since the conflict erupted in March 2011 and in recent months has been bolstering its forces in the area and reinforcing a fence along the frontier.
The rebels overran the border position near the abandoned town of Quneitra early Thursday, holding their positions for several hours before Syrian government troops retook it. The international peacekeepers who maintain a 40-year-old truce receive most of their supplies through that position from Israel.
Fierce gunbattles forced peacekeepers to seek shelter in a nearby base, and the Philippine military said one of its men serving in the force was wounded in the leg when a mortar or artillery shell struck the area. U.N. diplomats said an Indian peacekeeper also was injured.
In Vienna, Austrian leaders said the fighting made it necessary to withdraw their troops.
Defense Minister Gerhard Klug said he expected the withdrawal to be done within two to four weeks, but it is possible to complete it "within a few hours" if new violence threatened the soldiers' security.
"For the first time, it was not possible for the Syrian government to guarantee proper support of the U.N.," he said.
The decision dealt a heavy to blow to the 911-member U.N. force, which includes the 377 Austrian peacekeepers as well as 341 from the Philippines and 193 from India. Croatia withdrew its contingent in March amid fears they would be targeted.
Israel and Syria agreed to creation of the U.N. Disengagement Observer Force after Syria launched military action in 1973 in a failed effort to retake the Golan, which Israel captured in the 1967 Mideast war.
Secretary-General Ban Ki-moon said the United Nations is urgently looking for troops to replace Austrians and warned that any military activity in the zone separating Israeli and Syrian forces could jeopardize the long-held cease-fire.
The U.N. Security Council, in a statement, strongly condemned the intense fighting in the area of separation, urged respect for the 1974 disengagement agreement and called on all parties to allow the peacekeepers to operate freely.
The Israeli Foreign Ministry said it regretted Austria's decision and hoped that it would not lead to "further escalation in the region." It said it expected the U.N. to uphold its commitment.
Israeli military officials, speaking on condition of anonymity under military protocol, said several Syrians wounded in fighting were brought into Israel for medical treatment. Others who entered Israel were returned through alternative sites. It was not clear whether the wounded were fighters or civilians.
Israeli military officials said several errant shells landed in Israeli-controlled territory. Although no injuries were reported, the military restricted access to a main road running along the border for several hours and ordered farmers with fields in the area to remain indoors.
Nadav Katz, 65, of Kibbutz Merom Golan, a communal farm near the crossing, said the area was covered with smoke and residents could hear gunfire and mortar shells exploding nearby.
"We are concerned that things might evolve into something much harsher that will affect us," said Katz. "We like the idea that for 40 years the area was peaceful and quiet. Tourists have been coming, fields have been cultivated and children were born," he said.
Katz said he trusted Israel's army to defend the area, but residents felt betrayed by the fleeing U.N. troops. More than anything, though, he said people viewed the Syrian fighting as a terrible event. "People are simply sad over the slaughter," he said.
Israeli military officials played down the significance of Thursday's fighting. They said that Quneitra is important symbolically to Syria, given its history and location along a main route to Damascus. The town has been largely abandoned since the 1967 war, though the crossing is sometimes opened to allow Druse residents to export produce or cross into Syria to study or to marry their brethren.
Israeli officials say they have no interest in taking sides or getting involved in the fighting.
But the military has intervened on several occasions, firing at targets inside Syria in response to shelling that landed in the Israeli-side of the Golan.
In one such incident last month, Syrian troops targeted an Israeli jeep they said had crossed the cease-fire line into the Syria-controlled sector. Syria said it launched two missiles in self-defense, accusing Israel of violating the cease-fire deal.
The Israeli air force has also carried out several airstrikes in recent months on weapons shipments believed to be headed to Hezbollah.
Fighting between Assad's forces and mainly Sunni rebels has already spilled over Syria's borders into Turkey and Lebanon, where factions that support opposing sides have frequently clashed.
Moshe Maoz, a Syria expert at the Hebrew University, played down Thursday's incident. He called it a small victory for the Surian military and said little would change even if the rebels gained control of the crossing.
"It's symbolic, but neither al Qaida nor the mainstream groups are going to shoot at Israel because they know Israel will retaliate very heavily," he said.