An IDF vehicle in which Israeli troops were making a routine patrol along the border with Syria on Saturday night was hit by gunfire, apparently fired in error in their direction.

The Israeli troops fired back with “heavy fire,” Israel’s Channel 2 reported.

There were no injuries on the Israeli side, although the IDF vehicle was damaged, and no immediate word of injuries on the Syrian side. Later reports, however, said three Syrians had been killed.

The incident took place at Tel Hazeka, scene of several such incidents in recent days. It was not clear whether the errant gunfire came from Syrian government or rebel forces.

It came five days after at least two Syrian soldiers were reported injured Monday by an Israeli tank shell, fired deliberately at a mobile Syrian Army mortar battery that had just accidentally fired a mortar shell into Israeli territory in the Golan Heights. Israeli TV stations showed what they said was footage of a Syrian ambulance evacuating the injured soldiers. The Syrian casualties were believed to be the first such cases since the 1973 Yom Kippur War.

Israeli media reported that the decision to fire directly back at the Syrian troops was approved by the IDF’s Chief of the General Staff, Lt.-Gen. Benny Gantz.

Saturday night’s return fire followed the same policy of responding firmly and immediately to spillover violence, military sources said.

Last Sunday, when a mortar fired from the same area fell inside Israeli territory, the IDF fired a high-precision Tammuz anti-tank missile toward the Syrian mortar battery, but deliberately aimed adjacent to the Syrian troops, hoping that this would constitute sufficient warning to put an end to the errant mortar fire. When Monday’s mortar fall demonstrated that the warning had not been registered, the decision was taken to fire back directly at the source of Syrian fire, Israeli military sources said. The mortar shell that sparked Monday’s incident also landed near Tel Hazeka.

Israeli military officials still largely believe that the intermittent mortar fire into Israel from Syria is a spillover from intense fighting near the frontier between Assad’s army and rebel forces, and not an overt attempt to hit the Jewish state and draw Israel into the conflict. Notably, Syrian state media has not reported on the cross-border incidents.