In this tiny corner of Syria where the United Nations has a little-noticed foothold, peacekeepers stayed in their bunkers listening this month as several Syrians were reportedly killed by gunmen loyal to President Bashar Assad.
The UN Disengagement Observer Force did not publicize the incident, and there was no report from Israeli forces whose nearby hilltop observation units possibly saw or heard at least one of two gun battles in the valley below.
The Israel Defense Forces this week declined comment and there was no report of the incident in Croatia, whose president had visited Croat troops in the Golan just two weeks earlier.
This apparent desire to play down the threat reflects the tension gripping a small UN operation that ran successfully for 36 years and now faces a new challenge as a year-long Syrian uprising against Assad turns ever more violent.
"In the military we always have contingency plans," UNDOF commander Major General Natalio Ecarma told Reuters this week, while declining any comment on the Syrian crisis now lapping at the feet of his modest UN force with a limited mandate.
"Our purpose is to make sure that if anything happens, whatever it is, the tension does not escalate and friction between Syria and Israel does not happen," said the former Philippines Marines commandant, who has told his soldiers to prepare for "even more challenging days ahead" this year.
UNDOF numbers 1,050 soldiers from Austria, Philippines, India, Japan, Croatia and Canada. About 800 of them patrol on the Syrian side of the 1973 Golan Heights ceasefire line.
Their mandate is to oversee a dagger-shaped 400 square km "area of separation" where Syrian military forces are not allowed, but where Syrian security, police, customs officers and hunters may carry firearms.
It was in this zone three weeks ago that Austrian and Croatian troops at fixed observer posts heard firefights, at Jabbata al Khashab and Khan Arnabah, involving an estimated 140 Syrian gunmen, according to intelligence sources who disclosed the incident to Austria's Kurier tabloid a week later.
By using paramilitaries for a manhunt rather than uniformed troops, Syria could hope to avoid an overt violation of the disengagement agreement, to which Israel might respond.
UNDOF may protest to Damascus if it believes Syrian soldiers entered the area of separation with unauthorized military equipment such as machine guns and army trucks.No power to enforce
Austrian Defense Ministry spokesman Michael Bauer confirmed Kurier's report, stressing that the peacekeepers were never themselves targets. They halted patrolling and withdrew to the safety of their concrete shelters at Positions 32 and 37.
"We observe. We have no power to enforce," Austrian Major Stefan Eder told Reuters during a visit to UNDOF on Wednesday.
"There were no UN witnesses nor involvement," he said later in an emailed response to questions. "Two wounded male Syrians received first aid treatment from UNDOF soldiers."
The United Nations says at least 8,000 people have been killed in Syria. A Syrian official said this week that insurgents had killed more than 3,000 security force members,
With Assad no longer assured of total control, the exposed position of the UN force on the frontier may be a cause for concern at UN peacekeeping headquarters in New York.
Damascus is only 60 km from the fortified "Alpha Bravo Charlie Gate" where UNDOF shuttles between its logistics base Camp Ziouani, on the Israeli side of the line, and Camp Faouar inside Syria, where most of the peacekeepers are based.
It is not clear which way they would go if they had to be extracted, backing into Israel or flying out from Damascus.
No Syrian refugees have so far reached the solitary Golan crossing seeking access to Israel or UN protection, said Eder.
"There is for sure discussion" about a potential crisis developing on UNDOF's doorstep, he said. But decisions on what to do about any emergency "will be taken by a higher command".
"The Area of Separation, which is the main task of UNDOF, is free of any military forces, and UNDOF's task is to keep it free of military forces," he said, drawing a tacit distinction between army units and gangs of armed men.
UNDOF is lightly armed, with armored vehicles for self-defense only. Much of its upland operating area is a former battlefield, littered with destroyed tanks, where landmines and unexploded munitions were until recently the only hazard.
Some 50,000 Syrians live in towns and farm hamlets below in the area of separation, under Syrian civil administration.
Eder said "restriction of movement is increasing on the Syrian side because they are setting up checkpoints" -- an indication that not everyone in the area is an Assad loyalist.Intervention
Some powers want UN-secured humanitarian corridors or safe havens set up in Syria. They would need Assad's consent or a Security Council mandate for intervention - an unlikely prospect in the teeth of Russian and Chinese opposition.
The Security Council has not even discussed a peacekeeping force, but if one were ever authorized UNDOF could do little more than help with logistics and perhaps provide some personnel for the nucleus of a new operation.
The record of past UN peacekeeping operations suggests that UN military intervention in Syria to secure peace would require a force 50 to 100 times the size of UNDOF, with tanks and other heavy weapons, plus air supremacy and a secure logistics bridgehead, probably on adjacent foreign territory.
Syria's northern neighbor Turkey, the only Muslim member of NATO, is already sheltering thousands of refugees and is braced for a flood if the conflict intensifies.
Turkey has suggested creating a safe zone on Syrian land next to its border as one possible option. But Western allies have not backed a move that would mean using military force.
Israel says it would open the Golan gate to Syrian refugees if Assad falls. But Israel, still formally at war with Syria, seems an unlikely haven. Arab neighbors Jordan and Lebanon are just as close to southern Syrian cities as the Golan.
A refugee crisis, however, is not the only threat facing UNDOF. The 1974 Golan ceasefire line was quiet until May 2011, when flag-waving Palestinian demonstrators from Syria charged a fence and briefly reached Israeli-controlled territory.
A far more serious clash occurred in June, on the 44th anniversary of the 1967 Middle East war when Israel seized the Golan, the West Bank and Gaza. Israeli troops fired on Palestinian protesters who surged against the fortified boundary, and Syria said 23 were killed and 350 wounded.
Israel and the United States accused Assad of fomenting that clash to distract attention from his lethal crackdown at home.
There has been, as yet, no repeat of such demonstrations in 2012. But UNDOF was not able to turn back the rush on the disengagement line, and Israel has since built a taller, tougher steel fence on one stretch of the 75 km boundary.
GOLAN HEIGHTS (Reuters) -- Blue-helmeted United Nations peacekeeping troops patrolling a slice of Syrian territory to maintain a ceasefire with Israel face new risks as violence between Syrian government loyalists and rebels gets closer.