U.S. and coalition forces bombed the Islamic State 31 times on Saturday, retired Gen. James Mattis' first full day as secretary of defense, the Pentagon said in an news release.
The attacks occurred in both Syria and Iraq.
"Attack, bomber, fighter, and remotely piloted aircraft conducted 25 strikes consisting of 39 engagements," the Defense Department said of the strikes in Syria.
They occurred near Bab, Dayr Az Zawr, and Raqqa, ISIS's de facto capital, which was hit by 22 strikes. ISIS tactical units, headquarters, tunnels, fighting positions, vehicles, and oil well heads were all targeted.
In Iraq, six strikes consisting of 16 engagements occurred, according to Joint Task Force Operation Inherent Resolve, the U.S.-led operation fighting ISIS. The strikes targeted the terrorist group near Rutbah, Beiji, Kisik, Mosul, and Tal Afar. Attacks in Iraq hit tactical units, vehicles, weapons, a building, and other weapons related objects.