Fierce fighting was feared in Aleppo today as government and rebel reinforcements converged on the Syrian city.
On the fifth day of brutal clashes, the Syrian army turned its forces on Aleppo, ordering an armored column to advance on the country's second biggest city and pounding rebels there with artillery and attack helicopters, opposition activists said.
Reuters reported that as hostilities intensified near the Turkish border, Ankara said it was closing its crossing posts, although the United Nations said refugees fleeing Syria would be allowed through.
Thousands of government troops were being transferred to the city in a counteroffensive strike against rebel forces, said the Free Syria Army.
The New York Times reported that Aleppo was bracing for a major confrontation between government and insurgents today with hundreds of fighters from both sides streaming into the country.
The Syrian regime withdrew about 2,000 fully equipped troops, along with their tanks and artillery, from Idlib and sent them to Aleppo, about 40 miles away, the official said.
The struggle for Aleppo comes after a six-day rebel assault in Damascus, which culminated in the assassination of four top security officials in a bomb attack last Wednesday.
United Nations Secretary General Ban Ki-moon, speaking in Sarajevo on Wednesday, said, "Without unity, there will be more bloodshed. More deadlock means more dead," according to the Associated Press.
"That is why, here in the heart of a healing Bosnia and Herzegovina, I make a plea to the world: Do not delay. Come together. Act. Act now to stop the slaughter in Syria," he said.
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