For the first time since the outbreak of the Syrian uprising, two mortar shells exploded in the Mount Hermon area Wednesday morning.

There were no reported injuries or casualties. The area in the Hermon, the mountain range that straddles the Lebanese-Syrian border and the Golan Heights, was promptly closed to hikers for several hours on the Shavuot holiday.

The shells that landed inside Israeli territory were believed to be a result of fighting between Syrian President Bashar Assad’s regime and the rebels, not a planned attack on Israel. But Channel 2 reported Wednesday night that some in the security establishment believe the shelling was deliberately aimed at Israel.

Israel lodged a complaint with UNDOF, the United Nations Disengagement Observer Force, which oversees the buffer zone between Syria and Israel established by the Security Council in the wake of the Yom Kippur War. The mandate of UNDOF, which enforces the ceasefire between Israel and Syria, has been renewed every half-year since 1974.

Mortar shells fired from within Syria have landed in the Golan Heights several times in previous months, and Israel has often returned fire.

Last Monday, two shells reached the Israeli Golan Heights, but no injuries or damage were reported. They landed near the town of Ramat Magshimim. The next day, another mortar hit the southern Golan Heights as a result of the spillover from fighting in Syria, again without casualties or harm caused during the incident.

Before the start of the Syrian civil war, the northern Israeli territory had been relatively quiet for decades.