Brad Pitt's alleged child abuse investigation has been extended to look into further details whether the actor has additional instances of abuse that involves more of his six children with actress Angelina Jolie. The Los Angeles County Department of Children and Family Services has confirmed the extension, US Weekly reported.

Los Angeles County DCFS had previously just focused on the investigation with their 15-year old son, Maddox. According to reports, Pitt was allegedly "verbally and physically abusive" in front of his children while the whole family was on a flight. 

"They are looking at a history and pattern of behaviour," a source tells US Weekly. "They are looking at not only the original incident but other possible incidents surrounding it and more history."

US Weekly added that Maddox refused to attend a monitored visit with Pitt last week, with his other five siblings Pax, Zahara, Shiloh and twins Knox and Vivienne.

"He chose not to go and stayed with Angie," the informant told the US, "It wasn't full of joy and happiness."

According to a legal source, "it's normal for the DCFS to extend past the deadline to complete their work when an agreement exists between the parties." The insider adds that "it's standard" and denies the DCFS is looking at additional charges. 

The investigation was supposed to be closed by the end of October, but reports confirmed that investigation would further continue as the new allegation of multiple verbal cases of abuse has been raised. 

"The DCFS investigation is now going to continue for at least several more weeks," the source added. 

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

The source added that the FBI will have to investigate for another week and when finalized, "they will present the case to the prosecutor, who will evaluate whether they feel the need to bring charges against Brad."