Israeli warplanes have attacked a Palestinian "terrorist training base" inside Syria - the first Israeli attack on Syrian soil for more than 20 years.
The army destroyed the home of the suicide bomber
An Israeli army statement said the raid had targeted the Ein Saheb camp, near Damascus, which it said was used by several militant groups, including Hamas and Islamic Jihad.
The operation came in response to Saturday's bloody suicide attack on a restaurant in the northern Israeli port Haifa, which killed 19 people.
Syria has said the raid is a "grave escalation" and has called for an urgent meeting of the United Nations Security Council.
Egyptian President Hosni Mubarak, for his part, has condemned it as "aggression against a brother country".
Syria and Israel have long been at loggerheads over the Golan Heights, which Damascus lost to Israel in the 1967 war.
Syrian media have described Ein Saheb as a Palestinian refugee camp.
RECENT SUICIDE ATTACKS
9 September: 15 killed in Jerusalem and Tel Aviv
19 August: 23 killed in Jerusalem
11 June: 17 killed in Jerusalem
18 May: 7 killed in Jerusalem
5 March: 17 killed in Haifa
And a spokesman for Islamic Jihad - which claimed responsibility for the Haifa bombing - denied having "any training camps or bases in Syria or any other country".
A senior commander of another militant group, the Popular Front for the Liberation of Palestine, said the camp was one of his group's disused bases.
The army released video footage, apparently filmed by Iranian TV 18-months ago, showing a camp and underground munitions stores, which it said was the site targeted in the raid.
Earlier, the Israeli army demolished the home of the female Palestinian suicide bomber who carried out the Haifa attack.
It also launched missile attacks against two separate locations in Gaza City, including a Palestinian refugee camp.
Four young children and several Arabs were among the 19 people killed at the seafront restaurant in Haifa. About 50 people were injured in the attack, which wrecked the building.
It was one of the deadliest suicide attacks since the start of the Palestinian intifada three years ago.
The bombing came as Israel imposed a total closure of the West Bank and Gaza Strip for Yom Kippur - the day of atonement - which runs for 24 hours from Sunday evening.
Israeli Government spokesman Avi Pazner stressed that the air strike was not directed against Syria - but against Islamic Jihad.
But he said every country had to understand that it would be held responsible for harbouring any terrorists.
Israel released footage of what it said was the target of the raid
The Israeli raid marks a clear change in policy for Israel, which normally responds to Palestinian suicide attacks by striking against targets in the West Bank and Gaza.
Syria's Foreign Minister Farouk al-Sharaa said his country was capable of deterring
Israel but would exercise restraint over the raid.
Syria has been under pressure from the United States to clamp down on the activities of militant groups and says it has closed down offices of Hamas and Islamic Jihad in Damascus.
A spokesman for the UK Government in London said that "while Israel is entitled to take steps to protect itself against terrorist attack, these steps should be within international law".
German Chancellor Gerhard Schroeder, on a visit to Egypt, said the raid "cannot be accepted".