Iraqi officials say security forces have launched a helicopter-borne attack on the militant-held city of Tikrit.
The officials said Iraq Air Force helicopters landed inside the university stadium, leading to fierce clashes with Islamist militants.
State-run Iraqiya TV said the army troops killed "dozens of terrorists inside Tikrit University" and were now in control of the facility. The claim could not be independently verified.
Sunni militants led by the extremist Islamic State in Iraq and the Levant (ISIL) seized Tikrit, the hometown of executed dictator Saddam Hussein, two days after the June 10 launch of their offensive into northern Iraq.
Since then, the militants have overrun large parts of northern and western Iraq.
AFP says the Tikrit operation is the first announced use of helicopters to transport troops directly into combat since the crisis began.
Based on reporting by AFP and Reuters