Syria Conflict: Aleppo Showdown Could Be Imminent, U.N. Says

GENEVA — The U.N.'s human rights office warned Friday of an "imminent" showdown between government troops and opposition force in Syria's second-largest city, Aleppo.

The rebels are locked in fierce fighting with the government troops in Aleppo for six days and are bracing for an attack amid reports that the regime is massing reinforcements to retake the embattled city of 3 million.

Expressing her "deep alarm" at the situation, U.N. High Commissioner for Human Rights Navi Pillay said the reports coming out of Damascus "along with the reported build-up of forces in and around Aleppo, bodes ill for the people of that city."

Part of the reasons for that, she said in a statement read aloud to reporters Friday in Geneva by her spokesman Rupert Colville, are the "as yet unconfirmed reports of atrocities, including extra-judicial killings and shooting of civilians by snipers" during fighting in the suburbs of Damascus.

"And it goes without saying, that the increasing use of heavy weapons, tanks, attack helicopters and – reportedly – even jet fighters in urban areas has already caused many civilian casualties and is putting many more at grave risk," the statement said.

The statement also said that there have been clashes in Homs and Deir el-Zour.

A senior U.N. diplomat close to the mediation effort of international envoy Kofi Annan said they are "watching the situation in Aleppo with great concern."

"The ground is shifting. We use words like `It's fluid' – and it certainly is ... It has been a roller-coaster ride," the diplomat said, while speaking on condition of anonymity because of the delicacy of the negotiations among world powers on the U.N. Security Council.

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