GUVECCI, TURKEY—Syrian troops encircled a restive northern town on Thursday, an activist said, and more than 1,000 residents fled through a single escape route to Turkey where they camped outside on both sides of the lush frontier.

Syria’s authoritarian government has acknowledged losing control of parts of the northern province of Idlib, and what appeared to be an imminent assault in the town of Jisr al-Shughour would sharply escalate the upheaval that threatens the 40-year regime led by President Bashar Assad.

Dozens of Syrians were crossing into Turkey by the hour from Idlib, some on motorbikes and pickup trucks, some on foot.

“I don’t want to die. I want Bashar Assad to go,” said one Syrian teenager, who identified himself only by his first name, Ahmad, fearing reprisals from the Syrian government. Activists say more than 10,000 people have been detained since the uprising began in mid-March.

Syrian tanks were also deployed in the streets of Aleppo, the province that is home to Syria’s second-largest city of the same name, Turkish Prime Minister Recep Tayyip Erdogan told CNN-Turk television late Wednesday.

“There are tanks in the streets,” Erdogan said. “They seem to have lost control there.”

Aleppo has historic ties with Turkey and Erdogan said his government was taking measures to protect families there. Erdogan has said Turkey would accept all Syrians who flee, but he also has urged Syria’s government to adopt reforms aimed at ending the unrest.

In Geneva, Navi Pillay, the U.N.’s High Commissioner for Human Rights, accused Syria of trying to “bludgeon its population into submission” by attacking anti-government protesters with snipers, tanks and artillery.

The struggle over Jisr al-Shughour and Idlib is a critical test for the Assad family’s government, which said “armed groups” had killed 120 security forces in the area but has not commented on reports of a mutiny by some military units opposing the crackdown.

Ahmad and a few other teenagers from the town of Jisr al-Shughour spoke to an Associated Press reporter in Guvecci, where they came to collect food and blankets for their families still on the other side of the frontier. One villager said they came before dawn and would return at night to avoid detection by Turkish soldiers.

Muhammad, a 19-year-old, said hundreds of Syrians were camping just across the frontier “undecided whether to cross into Turkey or not.”

Muhammad accused the Syrian police and intelligence forces loyal to Assad and said: “The military units are not doing anything wrong.” He would not elaborate on reports that some troops had mutinied and joined forces with residents fighting back against the crackdown.

An elite Syrian military unit believed to be led by Assad’s younger brother, Maher, had all but surrounded Jisr al-Shughour, leaving open just one route to the border 20 kilometres away, according to activist Mustafa Osso.

“The reinforcements are complete and the army could storm the city at any moment,” Osso, who lives in Syria, told the Associated Press by telephone after talking to contacts in the area.

Al-Watan, a pro-government newspaper, reported Thursday that the army was mobilizing for a confrontation that would last for days in Idlib. It said troops faced an estimated 2,000 gunmen backed by young extremist villagers.

There was no way to independently verify the report. The Syrian government, which sharply restricts local media and expelled foreign journalists from Syria, has blamed recent violence on gunmen and religious militants.

Al-Watan also reported that people in Idlib were leaving home “to give the Syrian army a chance to enter all areas and confront the gunmen.”

The refugees in Turkey, mostly women and children, were seen resting in the shadow of pine trees within a fenced camp, where dozens of white conical tents are set up by the Turkish Red Crescent, the equivalent of the Red Cross.

Turkish ambulances were on standby at a border crossing in Yayladagi to rush any wounded refugees to hospitals. About 30 Syrians who have crossed the border were being treated for injuries suffered during clashes in Syria.

The Turkish province of Hatay has a sizable Arabic-speaking population. It gained independence from Syria in 1938 and joined Turkey in a plebiscite a year later. Families in some villages were split when the borders were finalized in 1948.

“We will keep our doors open to all Syrians seeking refuge in our country. It would be out of the question for us to close our doors at a time when deaths have intensified and our brothers are seeking the possibility of refuge,” Erdogan said Thursday.

The two countries share a 850 kilometre border, which includes several Syrian provinces, among them Aleppo.

A resident of the city of Aleppo, who spoke on condition of anonymity for fear of government reprisals, said tanks have been deployed in at least two towns in the province that have seen protests.

Osso, the rights activists, said there were no tanks in the city of Aleppo but in towns in the province. Osso, who is in contact with people in Aleppo, said there are security and police checkpoints.

Former British Prime Minister Tony Blair said Thursday that major democratic change in Syria is needed but warned that a revolution there would carry serious risks because of its potential impact throughout the volatile Middle East.

Blair said the NATO-led military operation in Libya was clearly necessary, and seems to be working, but said a more cautious approach is called for in Syria because of the uncertainty of what would follow a collapse of the Assad regime.