Israel downed a Syrian warplane over the Golan Heights on Tuesday in the first such incident in three decades and warned it would respond "forcefully" if its security is threatened.
It was the first time Israel had shot down a piloted Syrian plane since 1985 and drew a sharp response from Damascus.
Israel said the Syrian fighter jet had crossed the UN-patrolled ceasefire line on the Golan which it regards as its international border.
Pictures taken by AFP showed smoke rising from the Syrian village of Jubata al-Khashab which had been bombed by the warplane just moments before it was shot down by a Patriot surface-to-air missile fired by Israel.
The burning wreckage, also caught on camera, plunged down on the Syrian side of the ceasefire line.
Defence Minister Moshe Yaalon said the army had brought down "a Syrian fighter plane which approached Israel's sovereign territory on the Golan in a threatening manner, and even crossed the frontier."
Israel seized 1,200 square kilometres (460 square miles) of the strategic plateau from Syria during the Six-Day War of 1967, then annexed it in 1981 in a move never recognised by the international community.
A senior military official quoted by Israeli public radio said the Russian-made Sukhoi Su-24 had penetrated some 400 metres (yards) into Israeli air space before being shot down.
The downing came just three weeks after Israel shot down a drone over the Golan as heavy fighting raged on the Syrian-controlled side of the plateau, most of which has been seized by rebels fighting to overthrow President Bashar al-Assad.
The Assad regime has been hitting back with frequent air strikes in a bid to retake control. Some have been close to Israeli positions.
Damascus said the downing of its fighter jet showed Israel's support for the rebels on the Golan, who include Al-Qaeda loyalists who held 45 UN peacekeepers hostage for two weeks before releasing them earlier this month.
It described it as a "flagrant violation" of a UN Security Council resolution passed earlier this year calling for international action against jihadist groups.
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- Respond 'forcefully' -
But Yaalon warned that Israel would not tolerate any threats to its security and would respond "forcefully".
"We will not allow anyone, whether it is a state actor or a terror organisation, to threaten our security and breach our sovereignty," he said.
"We will respond forcefully against any such attempt, whether it is an error or intentional."
Since the uprising against Assad's rule erupted more than three years ago, the Golan has been tense, with a growing number of rockets and mortar rounds hitting the Israeli side of the ceasefire line.
Most of them have been stray, but there have been several incidents of intentional fire, one of which killed an Israeli teenager in June, and Israel has occasionally retaliated.
Some 510 square kilometres of the Golan remain under Syrian control, with UN peacekeepers overseeing a buffer zone along the armistice line stretching some 70 kilometres (45 miles) from Lebanon in the north to Jordan in the south.
Last week, the UN Disengagement Observer Force, which monitors the ceasefire, was forced to withdraw hundreds of its peacekeepers to the Israeli-occupied sector after rebels advanced on their positions.
Syria's UN ambassador accused the rebels of seizing UN weapons, uniforms and vehicles from the peacekeepers in order to set up a "safe zone" from which to wage attacks.
The UN Security Council held a special session on the deteriorating security situation on the Golan, at which members called on the rebels to withdraw from the buffer zone and return peacekeepers' equipment.
The session was convened over concerns for the safety of the UN force after 45 Fijian peacekeepers were held captive for two weeks by Al-Qaeda affiliate Al-Nusra Front. They were eventually released unharmed earlier this month.