At least 35 Daesh militants were killed in a failed attempt to flee western Mosul on Saturday, according to the Iraqi military.
Iraqi forces also detained six militants as they tried to escape from Mosul's Old City where security forces were closing in, the army said in a statement.
Army Captain Udai Mohamed said the Iraqi army has deployed dozens of snipers along the Tigris River in an effort to abort any Daesh attempt to attack Mosul's eastern side.
"We have a tip-off that besieged Daesh militants in the Old City were planning to storm eastern Mosul and cause chaos in some liberated areas," Mohamed told Anadolu Agency.
Meanwhile, 11 Daesh militants were reportedly killed in an airstrike on a Daesh convoy on the outskirts of Tal Afar city, west of Mosul, according to federal police officer Bahaa al-Meyahi.
Earlier this week, Daesh militants had executed 200 Turkmens in Tal Afar after holding them for around two months.
The Iraqi military remains engaged in a wide-ranging campaign – launched last October in coordination with a US-led air coalition – to recapture the entire city of Mosul, Daesh's last remaining stronghold in northern Iraq.