The United Nations says it is rushing aid to nearly 25,000 people fleeing Ramadi for the second time in a month after the Islamic State group seized the key Iraqi city.

The deputy spokesman for the U.N. secretary-general, Farhan Haq, told reporters Tuesday that most of those fleeing are headed toward Baghdad, with many trying to enter through security checkpoints.

He said the U.N. had not confirmed reports of militias turning people away, adding, "It would be an area of great concern if people are being pushed away from places of safety."

He says thousands of families had returned to their Ramadi homes when renewed fighting forced them to flee again. Haq says the U.N. and partners have helped more than 130,000 people over the past month alone.