United Nations: UN leader Ban Ki-moon appealed on Sunday to Israel and Syria to ease tensions on occupied Golan Heights boundary amid warnings that conflict in Syria could spread.

Israel fired warning shots into Syria after a mortar from the Syrian side hit an Israeli position in the Golan, officials said.

“The secretary-general is deeply concerned by the potential for escalation,” said the UN spokesman Martin Nesirky.

“He calls for the utmost restraint” and urges both side to uphold the 1974 accord which set up a ceasefire line and demilitarised zone which is patrolled by UN forces.

Syria and Israel must halt “firing of any kind” across the ceasefire line, added Ban, who has made repeated warnings that Syria’s 20-month old conflict could spill over into battles with neighbouring Israel, Lebanon and Turkey.

Ban was “concerned” by reports of clashes between President Bashar Al Assad’s forces and opposition rebels in the demilitarised zone in the Golan, said the spokesman. No injuries to civilians or UN personnel were reported, the UN said.

Senior officers in the UN Disengagement Observer Force (UNDOF) have demanded that the Syrian army withdraw from the zone, UN officials said.