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Assad sets referendum date as his forces attack Syria rebels

Inside Syria: NBC's John Ray reports from Zabadani, the Syrian town, that has been under siege from heavy shelling.

Syria's embattled President Bashar Assad on Wednesday said a referendum on a new constitution would be held in just 11 days' time, as his regime's forces moved on cities and towns across the country, including in capital Damascus.

Assad's government has ordered the vote for Feb. 26, state television reported. Amendments to the constitution were a key demand by opposition groups at the beginning of the 11-month uprising against Assad in March last year, but the groups now say they will accept nothing less than Assad's departure.

Meanwhile, the bombing of Homs, an anti-regime holdout, continued for the 11th day, while activists reported violence in the northwest of the country, The Guardian reported.

Rebels clashed with government forces in Altarib, near Aleppo, after reportedly blocking the road between Syria and Turkey with burning tires on Tuesday, the newspaper said.

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Syrian soldiers backed by armored personnel carriers also stormed part of Damascus, firing machine guns in the air, in the closest deployment of troops to the center of the capital in an 11-month uprising, residents and activists said, according to Reuters.

Troops from the Fourth Armored Division and Republican Guards searched houses, made arrests and erected roadblocks in the Barzeh neighborhood, a residential area north of the city center.

Residents said the troops were looking for opposition activists and members of the rebel Free Syrian Army, which has been providing security for protests against Assad in the district.

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"They have destroyed the facades of shops and turned back students heading to school. The raids are concentrating on Dahar al-Mustaha and Haret al-Bustan," Mazen, a university student, said by phone from Barzeh.

He said at least 1,000 soldiers had deployed in the district after the roads were sealed off, along with armored personnel carriers, armored jeeps and pickup trucks with heavy machine guns mounted on them.

In the besieged city of Homs, Syrian government forces are pummeling the city and activists there say it's the worst yet. NBC's Ayman Mohyeldin reports.

The largely Sunni Muslim district has been among the most active in the capital in the protest movement against the 42- year rule of Asssad and his father, the late President Hafez Assad.

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Pro-Assad militiamen from an Alawite suburb in mountains overlooking Barzeh had managed to suppress the demonstrations for months until the Free Syrian Army began protecting them in the last few weeks, residents said.

A firefight erupted last week in Qaboun neighborhood, which is adjacent to Barzeh, between loyalist forces and Free Syrian Army fighters, indicating the emergence of armed opposition to Assad in the capital.

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Msnbc.com, Reuters and The Associated Press contributed to this report.