The attacks took place on Friday: one drone hit a cargo terminal at Basra Airport, while two more hit the Burjesia oil facility, where American companies, among others, operate.
An oil field where BP operates has also been hit.
The information comes from security sources in Iraq. It is not stated who is behind the drone attacks.
On Friday, Iraq's government and leaders from the largely autonomous Kurdish region agreed on a statement demanding that "Iraqi territory must not be used as a base for attacks on neighboring countries."
Tehran has threatened to attack Kurdish areas if Kurdish soldiers participate in attacks against Iran.
