Iraqi troops have pushed deeper into Mosul after a two-week lull in the operation to retake the Islamic State-held city.
Backed by air strikes, Iraqi special forces, army troops and federal police launched a push on five neighbourhoods.
Smoke rose across the city as explosions and machine gun fire echoed through the streets.
Stiff resistance by the militants, civilians trapped inside their houses and bad weather have slowed advances in the offensive to recapture Iraq's second largest city, which is the extremist group's last urban bastion in the country.
Earlier this week, Lt Gen Abdul-Wahab al-Saadi, commander of the special forces in eastern Mosul, said his forces have been bolstered by reinforcements.