The website says the LAPD and the L.A. County Department of Children and Family Services are looking into alleged instances of verbal and physical attacks - and this was the reason for his divorce from Angelina Jolie.
TMZ alleges Pitt became drunk on a private plane and attacked his children.
According to their sources, after the plane landed, Pitt tried to escape in a commandeered fuel truck. He was later interviewed - and his children will be interviewed too.
"He takes the matter very seriously and says he did not commit any abuse of his children," a source near Pitt told TMZ.
"It's unfortunate that people involved are continuing to present him in the worst possible light."
Jolie cited "irreconcilable differences" as her reason for splitting with her partner of more than 11 years, with Pitt later telling media he was "very saddened" by the separation.
TMZ reported Jolie as saying she was "extremely upset" with Pitt's parenting methods.