Investigation Into Brad Pitt Child Abuse Allegations Continues as Family Safety Plan Extended

The investigation into child abuse allegations against Brad Pitt continues following Angelina Jolie's divorce filing.

ET has learned that the voluntary safety plan implemented by the Department of Child and Family Services last month that was set to expire on Oct. 20 has now been extended.

WATCH: Brad Pitt and Angelina Jolie's Divorce Battle and Federal Investigation: 4 Things We've Learned

ET can confirm that many people close to Pitt and Jolie will need to be interviewed by DCFS for this investigation. In addition to their staff and family, this will also include their friends.

Jolie and Pitt agreed to this temporary custody deal last month after the DCFS made its recommendations, a source familiar with the deal told ET at the time. The agreement -- also known as a structured decision making (SDM) safety plan -- is standard practice in any ongoing child welfare investigation. In addition, both Pitt and Jolie volunteered to participate in individual counseling. According to sources, Pitt also agreed to undergo drug and alcohol testing, though he was not required to.

WATCH: Angelina Jolie and Brad Pitt Strike Temporary Custody Deal, Includes Therapy and Random Drug Testing

Last week, ET confirmed that Jolie was visited by two FBI agents at her home in Malibu, California, to follow up on an incident that occurred on a private jet between Pitt and his 15-year-old son, Maddox. The incident in question occurred on Sept 14, during a family flight home from Europe, when Pitt allegedly got into an argument with their eldest son. A source previously told ET that reports of child abuse by Pitt were "exaggerated or untrue," and there was "no inappropriate physical contact" between the actor and his son.

The FBI tells ET that they are still "continuing to gather facts and will evaluate whether an investigation at the federal level will be pursued."

Jolie filed for divorce from the Allied star on Sept. 19, citing irreconcilable differences and requesting physical custody of Maddox and their five other children -- Shiloh, 10, Pax, 12, Zahara, 11, and twins Vivienne and Knox, 8. Pitt has yet to file a response to the dissolution of marriage papers.

WATCH: Brad Pitt Has Yet to File a Response to Angelina Jolie's Divorce Petition -- Here's Why

According to a source familiar with the Pitt-Jolie situation, he wants to "settle this privately like he has from the beginning."

Hear more in the video below.

_{-Additional reporting by Rande Iaboni}