Syrian troops backed by tanks and helicopters swept into the largely deserted town of Jisr al-Shughour on Sunday, crushing the last remnants of an open rebellion that had presented the regime with its stiffest challenge since widespread anti-government demonstrations erupted across the country nearly three months ago.

Reports from the town were difficult to obtain because telephone service was cut off and it appeared that almost no one remained behind. A resident who took refuge in the nearby hills said that tanks were destroying homes and that occasional bursts of automatic fire could be heard.

But it appeared that the few hundred residents and defected soldiers who remained behind to defend the town did not put up much of a fight, and either fled, or were arrested or killed.

“There is no one left in the town,” said the resident, who was contacted by telephone and spoke on the condition of anonymity.

“This was a completely one-sided battle,” said another activist in Damascus, who also spoke on the condition of anonymity.

The Syrian military’s apparent success in regaining control of Jisr al-Shughour may prove short-lived, however. The week-long operation to stamp out dissent in this remote rural area has already backfired, by alienating powerful neighbor Turkey and adding an international dimension to a crisis that has been treated by global powers as a domestic Syrian problem.

At least 5,000 Syrians have crossed into Turkey, and thousands more are thought to be hiding out in hills along the border after fleeing the Syrian military's advance through the countryside. Syrian troops burned crops and destroyed homes, according to refugees arriving in Turkey.

Turkey, along with many world powers, had been muted in its criticism of President Bashar al-Assad’s regime, urging him to accelerate reforms but not pressuring him to step down.

But on Friday, as Syrian refugees poured into Turkey, Prime Minister Tayyip Erdogan sharply reversed his position. He lashed out at the “barbarity” of the unit commanded by Assad’s brother Maher, which is thought to be behind the crackdown.

“After all that has happened, Turkey can no longer defend Syria,” Erdogan told a Turkish television station.

For Assad, that was “a significant blow,” said Amr al-Azm, an assistant professor of Middle East history at Shawnee State University in Ohio, who is also active in the Syrian opposition.

The operation in Jisr al-Shughour resembled earlier efforts to crush uprisings in the southern town of Daraa and in the town of Tal Kalakh near the Lebanese border, with one key difference, he said.

“The difference is that Jisr al-Shughour is very close to the Turkish border, and on the other side you’ve got a Turkish government that’s at best unfriendly and at worst hostile to the Syrian regime,” he said. Now Syria can’t count on its neighbor to the north.

“The Turkish-Syrian border is huge, and that border is going to leak like a sieve,” in terms of logistical support and equipment such as cellphones and other technology that has been used to support the protest movement, he said.

Just as worrying for Assad are the indications that some form of mutiny by Syrian security forces took place in the town last weekend. Military reinforcements were rushed to the town after Syrian state media reported the deaths of 120 soldiers allegedly at the hands of “armed gangs.” But defected soldiers have told Arabic news channels in southern Turkey that the troops were killed by their superiors after they defected.

Syrian troops on Sunday uncovered the bodies of 10 uniformed soldiers from a grave outside a military police building in the town, according to an Associated Press reporter traveling with the troops. He said at least four of the soldiers had been either beheaded or killed by ax blows to the head. The building had been burned, and there were bloodstains on the floor.

Although it is clear that some form of violent confrontation occurred in the town — where some protesters acquired arms and banded together with defected soldiers to oust government forces — the opposition movement insists it is determined to remain peaceful.

The Syrian regime is trying to portray the democracy demonstrations across the country as an armed rebellion, and protesters realize that taking up arms would play into the government’s hands, Azm said.

“Everyone agrees that this is not what we want to go for,” he said. “Any effort to do that would be counterproductive. The regime holds all the cards, and it would give them an excuse to use excessive force.”