Israel on Sunday fired two Patriot missiles at a drone that “infiltrated” from Syria, the Israeli army said.

The missiles missed the drone which “returned to Syria” after the incident in the central Golan Heights, where the demarcation line between the two countries is located, the military said.

“Moments ago two Patriot air defense missiles were fired towards a drone which infiltrated Israeli airspace from Syria,” the military said in a statement on Sunday evening.

Sirens sounded in the area.

Earlier in the day, a grenade explosion killed two Israeli soldiers and wounded three others near a military outpost in the Golan Heights, the army said in a statement.

The incident occurred at Mount Hermon near the demarcation line with Syria. Details on how the Israeli grenade went off were being investigated.

The two soldiers killed were identified as Staff Sergeant Hussam Tafesh, a 24-year-old Druze, and Sergeant Shlomo Rindenow, 20 and originally from the United States.

Israeli media reported that one of the soldiers exited an army vehicle holding the grenade and approached another soldier standing outside the outpost when it exploded.

Stray fire from Syria’s five-year civil war has occasionally landed on the Israeli side of the demarcation line.

Earlier this month, the Israeli army attacked two Syrian military targets on the Golan Heights after stray Syrian fire damaged the security fence along the line.

While Israel has sought to avoid being dragged into the Syrian civil war, it has attacked Syrian military targets when fire from the conflict spills over into its territory.

Prime Minister Benjamin Netanyahu also acknowledged in April that Israel had attacked dozens of convoys transporting weapons in Syria destined for its Lebanese enemy Hizbullah.

Israel seized 1,200 square kilometers of the Golan Heights from Syria in the Six-Day War of 1967 and later annexed it in a move never recognized by the international community.