A spokesman for Ban Ki-moon says the UN secretary general is gravely concerned about reports of an Israeli air strike on Syria but cannot independently verify what happened.
Deputy UN spokesman Eduardo del Buey said on January 31 that Ban is also calling "on all concerned to prevent tensions or their escalation in the region."
Ban's comments came after Syria lodged an official complaint with the United Nations over what it said was an Israeli air strike on a military research center near Damascus.
State media said the Foreign Ministry summoned the head of the UNDOF peacekeeping force in the Golan Heights.
Syria's army said the apparent raid on January 30 killed two people and wounded five.
It also denied reports that trucks carrying weapons bound for Lebanon were hit.
Israel has not commented on the claims.
Damascus says the Israeli raid is a violation of a 1974 disengagement accord between the neighboring countries. Israel has not commented.
A Syrian official and Iranian deputy minister suggested there could be retaliation.
Russia said it is taking "urgent measures to clarify the situation in all its details."
Russia and Iran are close allies of Syrian President Bashar al-Assad’s regime.
Based on reporting by AFP and Reuters