A mortar shell fired from Syria fell in the Golan Heights near Tel Fares on Tuesday evening, an IDF spokeswoman confirmed. No injuries or damage were reported.
"The army is still sweeping the area. The UN has been notified of the incident," the spokeswoman added.
A few minutes after the mortar landed, IDF soldiers on patrol on the Syrian border reported hearing gunfire near Tel Hezka. No injuries were caused.
Following the incident, the IDF fired tank shells at the source of shots. The target was accurately struck, the IDF said.
It remains unclear whether the mortar was fired deliberately into Israel, or as part of an exchange of fire between army forces loyal to the regime of Basher Assad and rebels.
The UN Security Council voiced concern last week about the increasing spillover into the Golan Heights of the Syrian civil war.
Earlier on Tuesday, Defense Minister Moshe Ya'alon toured the Syrian border and vowed that Israel would prevent the proliferation of weapons "that could threaten us in the future" to radical elements in Syria.
"But we're not getting involved so long as this does not harm our interests. When it harms our interests, whether through Grad rocket fire from over the border, whether it is intended to hit our territory or not, we respond in order to silence the source of the fire," Ya'alon added.
The comments came hours after Arab media reports said Syrian rebels, including the jihadi Jabhat Al-Nusra group, seized the town of Al-Safira near Aleppo, which is reportedly close to a large military facility that stores chemical arms.
The area has been marked by previous fighting between the Syrian army and rebel forces in recent months. JPost.com staff and Reuters contributed to this report.