BAGHDAD — Iraq sent battalions of reinforcements on Wednesday to secure neighborhoods in Ramadi recaptured from the Islamic State, as soldiers continued an offensive for a second day to try to take full control of the city.

The reinforcements, including Sunni Muslim tribal fighters trained by the United States, were intended to allow the first wave of troops to continue pushing toward a government complex in the center of Ramadi held by fighters for the Islamic State, also known as ISIS or ISIL, a senior military commander told Iraqi state television.

Soldiers were also fighting to control a district in southern Ramadi along the Euphrates River, officials said.