Fears of massacre as Syrians shell Aleppo

BEIRUT -- International concern about a potential massacre was mounting Friday as Syrian troops bombarded the besieged city of Aleppo with artillery, strafed it with aircraft and reportedly pulled in major reinforcements ready to crush the outgunned rebels.

The battle is one of the most important of the 17-month-old uprising. With a population of about 3 million, Aleppo is Syria's largest city and commercial hub, a key pillar of support for President Bashar Assad's regime.

The rebels controlled several neighborhoods but were facing reports of troops and tanks massing outside the city. The nonstop fighting in Aleppo already has claimed the lives of at least 145 rebels and civilians in the last six days, according to the Britain-based Syrian Observatory for Human Rights.

UN High Commissioner for Human Rights Navi Pillay expressed "deep alarm," saying in a statement that the "reported buildup of forces in and around Aleppo bodes ill for the people of that city . . . 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."

In at least two areas formerly held by rebels, Qubair and Houla, hundreds of civilians were killed after pro-regime militias moved in, activists reported.

It has been a difficult two weeks for the Syrian government with rebel assaults first on the capital, Damascus, and then on Aleppo, as well as several high-profile defections and a bomb that killed four top security officials.

The government, however, struck back and quashed the assault on the capital with a combination of heavy weapons and house-to-house searches. Scores of people were killed.

Opposition activists said they expected similar tactics in the coming days to keep Aleppo from falling into rebel hands.

"I think there will be a huge massacre in Aleppo," said Michel Kilo, a veteran opposition figure living in exile in Paris. "There will be a terrible revenge against civil society." He said all of Aleppo, once believed to be a regime stronghold, was revolting against Assad's regime.

British Foreign Secretary William Hague and UN Secretary General Ban Ki-moon called on Assad to immediately halt the attack on Aleppo.