BAGHDAD (AP) — Two Iraqi military officers say the advance of troops has slowed in the last push to drive Islamic State group militants from remaining pockets of Mosul.

The officers, who spoke Sunday on condition of anonymity in line with regulations, say IS militants have deployed snipers, suicide car bombers and suicide attackers on foot. They described the advance on Mosul's Old City as "cautious" and the clashes on Sunday as "sporadic."

On Saturday, U.S.-backed Iraqi forces began a new offensive to recapture the Old City from three directions. Hours after announcing the push, the government said two military officers were killed in clashes in the Shafaa neighborhood on the Tigris River.

Mosul's eastern half was declared liberated in January and the push for the city's west began the following month.