The national flag carrier was scheduled to operate flights from September 27 till October 5 to Najaf and Baghdad from Karachi, Lahore, and Islamabad.
The rockets come two days after a US airstrike killed Iran’s top general Qassem Soleimani as he was being driven to the airport in Baghdad.
The rallies have gathered despite temporary curfews, threats of arrest and violence that has left nearly 240 people dead.
The authorities accused unidentified snipers of shooting into the crowd
A bomber detonated an explosive belt surrounded by security forces.
Youth make up around 60 percent of Iraq's nearly 40 million people.