JERUSALEM — Several mortars fired by Syrian government troops targeting rebels hit the Israeli-occupied Golan Heights on Tuesday but no one was hurt in the shelling, the Israeli military said.

The incident marks the second time Syrian mortars have landed on the border area since Syria's crisis erupted 18 months ago. In July, mortar shells fell about one kilometer (half a mile) from the Golan boundary.

Tuesday's shells were not aimed at Israel but at rebels in Syrian villages close to the Golan frontier and were part of the ongoing fighting in Syria, said an Israeli army spokesman, speaking on condition of anonymity in line with military regulations. Israel Radio said there was heavy fighting reported in the area of Quneitra in Syria, near the Israeli-patrolled border.

The Israeli army says it has filed a complaint to the United Nations peacekeeping force that patrols the tense region between Israel and Syria. There have been concerns in Israel that violence could spill over from Syria, and that the long-quiet frontier area could become a new Islamist front against the Jewish state.

The Israeli-annexed Golan Heights was captured from Syria in 1967.