Angelina Jolie was questioned by the FBI for four hours over the Brad Pitt private plane incident.

Brad Pitt and Angelina Jolie

Brad Pitt and Angelina Jolie

Brad is alleged to have gotten "verbally abusive" and "physical" with their son Maddox, 15, while under the influence of alcohol during a flight on September 14 and Angelina filed for divorce just days later.

After an anonymous source reported the alleged incident, the FBI got involved as they have jurisdiction because it occurred mid-air.

A source told Us Weekly: "The agents wanted a breakdown of everything that happened from when the plane took off to when it landed. Angelina fully cooperated."

The insider added that the FBI "will likely investigate for another few weeks". After that they "will present the case to the prosecutor, who will evaluate whether they feel the need to bring charges. It could potentially be months".

Yet both Brad and Angelina are eager to avoid a court case, with the insider explaining: "Neither side wants this to go to court because everything the FBI and DCFS investigated will potentially be made available to the public, which would be bad for the entire family."

And it was later reported that "Maddox suffered no injuries and some witnesses on the jet say Brad's contact with the boy was inadvertent".

Meanwhile, it has recently been claimed that the Department of Children and Family Services have extended their investigation into Brad.

Angelina, Brad and their children - Maddox, Pax, 12, Zahara, 11, Shiloh, 10, and eight-year-old twins Knox and Vivienne - have all been previously interviewed and TMZ reports that the "DCFS has now expanded its investigation to other alleged incidents".

Angelina and Brad have agreed on a parenting plan, giving Angelina temporary physical custody over the kids with Brad allowed to visit them under the supervision of a therapist.