Emergency sirens went off in several communities in the northern Golan Heights Wednesday morning.

The IDF Spokesman said that security forces have been combing the area but so far, have not found traces of explosions. It is likely that what set off the sirens were mortar shells that struck near the border, but inside Syrian territory.

The sirens blared at Ortal, Alonei Habashan, Merom Golan, Eyn Zivan and Keshet, at 11:46.

At first, it was estimated that the sirens were set off by stray mortar shells that “spilled over:” into Israeli territory, as fighting rages in Syria.

There has been concern in recent days that Druze villagers in Syria who are coming under attack from ISIS will stream toward their brethren inside Israel’s Golan Heights. 

The IDF on Tuesday afternoon temporarily declared a region in the north-east of the Golan Heights near the border with Syria as a “closed military territory,” but just a short time later cancelled the closed zone opening it back up to the public.

The order had blocked access for citizens who do not live in the region, so as to allow IDF forces to freely move in routes adjacent to the border.

“The IDF is closely following the developments in the fighting in Syria and on the Golan Heights border,” the IDF released in a statement.

It added that the army “is working to preserve the security in the area.”

Despite the statement focusing on Syrian fighting, the security services stressed that the closure of the area is meant to prevent gatherings of Israelis adjacent to the border barrier which would interfere with ongoing routine IDF activities, and stated that the move was not directly taken as a countermeasure to the fighting in Syria.

There have been numerous instances of “spillover” of mortar shells and machine gun fire as rebel forces, regime forces and Islamic State (ISIS) duke it out over the border in the Syrian side of the Golan.