(CNN) -- Fighting raged in a major Syrian city Tuesday, with at least two people killed and several others wounded, an activist group said. Clashes erupted between protesters and security forces in Homs, according to the Local Coordination Committee in Syria, a network of activists that promotes and documents demonstrations across the country. They occurred in al-Khalidiya neighborhood, and video said to be from the Homs unrest shows protesters running and throwing rocks and contains sounds of heavy gunfire. CNN cannot independently confirm the information. Demonstrations critical of the government began in the southern city of Daraa and were swiftly suppressed by security forces. Anti-government fervor caught on nationwide as more protests were met with tougher crackdowns.
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NEW: Fighting erupts in the Syrian city of Homs
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U.S. ambassador was among those visiting northern Syria
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A human rights official says dozens of peaceful protesters are arrested in Aleppo
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More than 10,000 Syrian refugees reportedly have crossed the border into Turkey
Meanwhile, state TV showed images Tuesday of thousands joining pro-regime rallies in Daraa, @placeholder and Homs.