Ankara - A Syrian general and 38 other soldiers defected to Turkey overnight, state television said on Monday, days after Syria shot down a Turkish warplane, escalating tensions between the two neighbours.
Turkey has summoned a Nato meeting for Tuesday to agree a response to the downing of its military reconnaissance jet in what it says was an attack without warning carried out over international airspace.
Turkey's cabinet was to meet on Monday to discuss Friday's attack, which lent a more menacing international dimension to the 16-month-old uprising against President Bashar al-Assad. Britain said it could press for more serious action at the United Nations Security Council.
European Union foreign ministers meeting in Luxembourg called for a calm response from Turkey, saying they would increase pressure on Assad. There seemed little appetite, however, for any military retaliation against Syria
"Military intervention in Syria is out of the question," said Dutch foreign minister Uri Rosenthal. "It is not a matter of consideration for the Dutch government. That is also at stake in the ... context of Nato."
The new defections from Assad's armed forces could encourage those awaiting a disintegration of Assad's army. But there has been little indication of any broader trend to desertion in the senior ranks of the armed forces, bound often to Assad by their Alawite background.
A Syrian general, two colonels, two majors, a lieutenant and their families - altogether 199 people - crossed the border into Turkey overnight, CNN Turk said. Thirteen Syrian generals are now in Turkey which is giving logistical support to the Free Syrian Army, though Ankara denies arming the rebels.
Turkish newspapers welcomed Prime Minister Recep Tayyip Erdogan's decision to invoke an article in the Nato alliance's founding treaty providing for urgent consultations if a member considered its security interests threatened.
"Turkey has moved into action" both Milliyet and Vatan newspapers declared in headlines under the Nato flag. Liberal Radikal daily said: "No accident, an attack".
The search for the aircraft and two messing air crew continued in the eastern Mediterranean, close to the maritime borders of both countries.
But analysts thought it unlikely that Turkey, even with the second biggest army in Nato, some half a million men under arms, would opt, at least for now, for military action against Syria.
"I don't think Turkey's response will be a military one," said Cagri Erhan, a professor of political science at Ankara University. "War is not one of the options. Turkey will act in line with measures taken within Nato."
"I'm not of the opinion that Turkey will immediately respond militarily," agreed Beril Dedeoglu of Galatasaray University. "But if there is another action, then there will certainly be a military response, there is no doubt."
Syria argues that the Turkish aircraft was in Syrian airspace flying low and fast when it was attacked. It said it was not clear until after it was shot down that it was Turkish.
The United Nations has said more than 10 000 people have been killed by government forces, while Syria has said at least 2 600 members of the military and security forces have been killed by what it calls foreign-backed "Islamist terrorists".
Fierce fighting continued inside Syria, which has a 900km border with Turkey, with rebel fighters killing dozens of soldiers in the last few days as they fought against army attacks on towns and villages in central, north and eastern Syria in the last several days, according to opposition sources.
Syrian tanks and artillery shelled the eastern city of Deir al-Zor, killing at least 20 people on Sunday in the second day of heavy bombardment in the country's main oil-producing region, opposition activists said.
"Regime forces have dismantled their roadblocks from inside of Deir al-Zor after incurring heavy losses from rebels. They have withdrawn from residential areas and are now shelling the city from the outskirts. The victims are mostly civilians," a source at a hospital in Deir al-Zor said.
Flood of refugees
The official state news agency said "terrorists" abducted a state-appointed head of clerics in Deir al-Zor and blew up an oil pipeline passing through the province.
The Syrian Network for Human Rights, an opposition activists' organisation that monitors the crackdown on the 16-month revolt against Assad's rule, said loyalist forces on Sunday killed another 70 people, mostly civilians and soldiers who had tried to defect, elsewhere in the country in shelling, military raids and summary executions in the provinces of Homs, Hama, Idlib, Deraa and suburbs of Damascus.
The intensification of the fighting has raised fears in Turkey of a flood of refugees and a slide into ethnic and religious warfare that could envelop the region. Ankara, like the West, is torn between a wish to remove Assad and the fear that any armed intervention could unleash uncontrollable forces.
US Secretary of State Hillary Clinton called the attack on the Turkish F-4 jet "brazen and unacceptable" and said Washington would co-operate closely with Ankara to promote a transition in Syria.
While Turkish newspapers have railed against Assad, Erdogan, not always known for his emotional restraint, has eschewed bellicose rhetoric.
The prime minister, who turned against former ally Assad bitterly after he refused his advice to bow to demands for democratic reform, seemed to back away from any suggestion of an armed response.
If he sought some kind of retaliation from the Nato meeting set for Tuesday, he could have invoked another article on mutual defence. That he did not, suggests the reaction will remain at least for now, on the diplomatic stage.
The foreign ministry said Turkey knew where the wreckage of the RF-4 Phantom jet lay, 1 300m under water, but had not yet found it. Minister Ahmet Davutoglu said the search continued for the two crew members.
He said the jet had been clearly marked as Turkish and dismissed Syria's assertion it had not identified the aircraft, flying low and very fast, before opening fire.
Russia, which along with Iran is Damascus's chief ally, has provided most of Syria's arms and has access to a deep water naval base in the country.
Davutoglu said he planned to set out Turkey's case to the UN Security Council where Western powers are seeking, against Russian and Chinese opposition, to push through a motion that could allow stronger measures against Assad.
Moscow has made clear it would continue to veto such a move, which it fears could undermine its interests in Syria and wreak anarchy. That apparent inevitability forces the focus for any stronger action on Nato.