There are conflicting reports of heavy fighting in Syria's largest city, Aleppo.
Government forces have entered one part of the city, Salah al-Din.
Battles are being fought on narrow streets.
Both sides are claiming victories.
Achilles Demetriou is in a a freelance photo-journalist and he's in the northern section of Aleppo.
He says people in Aleppo are expecting a larger assault, and they're desperate to get out.
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