Almost 12,000 Syrians are now known to have fled across the border to Turkey following the state crackdown on months of protests.
The local government in Turkey's Hatay province said the new wave of refugees, who crossed the border from makeshift camps inside Syria, brought the total number now registered in Turkish camps to 11,739.
Syrian troops gathered near the Turkish border yesterday, raising tension with Ankara as President Bashar al-Assad increases the use of military force against the three-month-old popular revolt.
Turkey said the two countries' foreign ministers had consulted by telephone.
Syria's ambassador to Ankara was later summoned to the foreign ministry, demonstrating further how disturbed Turkey is over events in its southeast neighbour.
US Secretary of State Hillary Clinton said the reported move by Syria to surround and target the town of Khirbat al-Joz - just 500m from the Turkish border - marked a worrying new phase of Syria's attempt to quash anti-government protests.
'If true, that aggressive action will only exacerbate the already unstable refugee situation in Syria,' Mrs Clinton said.
Witnesses said hundreds of terrified refugees crossed into Turkey to escape an army assault.
Syrian troops stormed the village of Managh, 15km south of the border and just north of the commercial hub of Aleppo, according to residents.
'I was contacted by relatives from Managh. Armoured personnel carriers are firing their machineguns randomly and people are fleeing the village in all directions,' an Aleppo resident said.
Mainly Sunni Turkey has become increasingly critical of Mr Assad, who belongs to Syria's Alawite minority, an offshoot of Islam, after previously backing him in his drive to seek peace with Israel and improve relations with the US.
Mr Assad also opened the Syrian market to Turkish goods.
Meanwhile, human rights activists said that at least 15 protesters were killed when Syrian security forces opened fire on anti-regime rallies today.
The violence came as thousands of protesters took to the streets across Syria after the weekly Muslim prayers calling for the fall of the autocratic regime of President Bashar al-Assad.
The demonstrations were in response to a call by the Facebook group Syrian Revolution 2011, one of the motors of the protests, under the banner, 'Fall of legitimacy'.
Syria's state television blamed civilians deaths in Barzeh on 'armed men'.
