Israeli military fired 'warning shots' into Syria, Saturday.
According to Reuters, "Israeli forces fired "warning shots" into Syria on Sunday after stray mortar fire from fighting between Syrian forces and rebels hit the Israeli-occupied Golan Heights, Israel's military said."
Though Israel quickly remedied the situation, top officials did threaten to ramp up retaliation if attacks continued.
The reason for Israel's distrust of Syria is well known.
"They [Israelis] have feared that the instability in Syria over the past 19 months could spill across the border into Israel, particularly as President Bashar Assad's grip on power grows increasingly precarious," the Associated Press said.