Prime Minister Benjamin Netanyahu said Israel had "thwarted an attempted sabotage on the Syrian front".
This article from Australia's ABC, explains what's happening.
Israeli fighter jets and attack helicopters have struck military targets in southern Syria belonging to the Syrian Army hours after thwarting an infiltration attempt from Syria by suspected militants trying to plant explosives, the Israeli military says.
In a rare statement acknowledging strikes in neighbouring Syria, the Army said the targets included "observation posts and intelligence-collection systems, anti-aircraft artillery facilities and command and control systems" in Syrian bases.
Syria acknowledged the strikes, saying Israeli helicopters fired missiles at Syrian outposts and reported unspecified "material damage".
The incident comes amid heightened tension on Israel's northern frontier following a recent Israeli airstrike that killed a Hezbollah fighter in Syria and anticipation that the militant Lebanese group would retaliate.
'Harm all those who try to harm us'
Lieutenant-Colonel Jonathan Conricus, a military spokesman, said Israeli troops spotted "irregular" activity in the Golan Heights.
Israeli troops opened fire on the suspected militants, some of whom were armed, after observing them placing the explosives on the ground, Lieutenant-Colonel Conricus said.
There was no official confirmation that the four suspected attackers were killed but a grainy video released by the Army shows four figures walking away from barbed wire marking the frontier.
The four then disappear in a large explosion that engulfs the area.
The Israeli military did not say if the four were suspected of having ties to Iran or Hezbollah, two Syrian allies.
However, Lieutenant-Colonel Conricus said Israel held the Syrian Government responsible for the incident.