Brad Pitt got into an argument with his son Maddox last week on the family's flight home from France according to a source close to the actor and his estranged wife Angelina Jolie, which led to her decision to file for divorce.
The actor and his 15-year-old son were at odds for unknown reasons, but Pitt did not touch the teenager at any time claims the source.
The source went on to say that allegations of abuse against the actor, both verbal and physical, have been "exaggerated or fabricated".
Pitt is now being investigated by the FBI and social services in Los Angeles.
A statement from the FBI said: "In response to your inquiry regarding allegations within the special aircraft jurisdiction of the United States; specifically, an aircraft carrying Mr. Brad Pitt and his children, the FBI is continuing to gather facts and will evaluate whether an investigation at the federal level will be pursued."
On Thursday morning, a police car was seen arriving at the Jolie-Pitt compound in the Hollywood Hills, where Pitt is believed to be staying while Jolie and the children are at a Malibu rental home.
The family is said to have been on a flight home from France when he allegedly became 'wasted' and started 'screaming' before continuing the 'rant' on the tarmac when the plane landed, trying to leave the scene in a fuel truck.
TMZ was the first to report that this alleged episode prompted Jolie to split from the 52-year-old the next day and then file for divorce.
The FBI is investigating the incident because it allegedly happened mid-air. An LAPD spokesperson told Fox News that because the incident allegedly happened on an airplane, the investigation is out of their jurisdiction.
US Weekly is reporting that the anonymous call came from someone on the plane as it headed towards Los Angeles, which led to members of DCFS meeting the family on the tarmac and questioning them on the scene.
The LA County Department of Children and Family Services told KTLA reporter and anchor Wendy Burch there is an investigation into child abuse claims, but a spokesman later told DailyMail.com they have strict laws that don't allow them to confirm or deny the subjects of investigations.
A colleague of the couple meanwhile tells Access Hollywood that while Jolie wants the children to have a relationship with Pitt, there are no plans for visitation between the six kids and their father at this time.
And while the divorce did not come as a surprise to Pitt, he was thrown off by the time according to those close to the actor.
'He was appealing to her to do this quietly - not to save the marriage but to consider the well-being of the children - and it was ignored,' a source close to the actor told People.
The source added: 'There was clearly a breaking point, where she'd just had enough. He may have been broken himself and said he couldn't go on, and she reacted. This has been difficult for a while.'
A source close to Jolie meanwhile said: 'Things built and built over time - it wasn't any one thing.
'She's loved this man for several years, and [divorce] is not something you do impulsively.'
That source said that in the end Jolie did 'what she needed to do.'
The Jolie source added however: 'They have six kids together and are always going to be in each other's lives.'
Jolie did not respond to a request for comment while a spokesperson for Pitt reiterated the actor's statement from earlier in the week in which he said: 'I am very saddened by this, but what matters most now is the well being of our kids. I kindly ask the press to give them the space they deserve during this challenging time.'
Both sides have been adamant that there was no extramarital affair and that both are committed to their children, despite false reports that Pitt had engaged in a relationship with his Allied costar Marion Cotillard.
On Wednesday, Cotillard revealed that she is pregnant with her second child and vehemently denied having an affair with Pitt.
Cotillard, 40, wrote a lengthy Instagram message to make the announcement and to dispel rumours on Wednesday before confirming that her partner of eight years Guillaume Canet is the father of her unborn child.
'This is going to be my first and only reaction to the whirlwind news that broke 24 hours ago and that I was swept up into,' the actress said in her post.
'I am not used to commenting on things like this nor taking them seriously,' she continued, 'but as this situation is spiraling and affecting people I love, I have to speak up.'
She concluded her message by wishing Brad and Angelina Jolie well.
'Finally, I do very much wish that Angelina and Brad, both whom I deeply respect, will find peace in this very tumultuous moment. With all my love, Marion.'
Her well wishes come despite a source telling DailyMail.com that Jolie was so jealous of Cotillard on the Allied set that she would not even speak to the French star.
Angelina completely ignored Marion on the set, and when Marion tried to talk to her she just looked the other way,' said the source, who is close to both Jolie and Pitt.
'Marion was devastated, here she is thinking she is going to meet this great UN ambassador and instead Angelina refuses to speak to the woman because of her own jealousy.'
Jolie filed for divorce from Pitt on Monday for 'the health of her family', two years after they wed at their French estate Chateau Miraval.
The actress filed papers citing irreconcilable differences as the reason for the split and asked for physical custody of the couple's three biological children as well as their three adopted children - Maddox, 15, Pax, 12, and Zahara, 11.
Pitt is said to have been furious over Jolie's appointment of Arminka Helic, 48, and Chloe Dalton, 37, two former political aides to British politician William Hague. A source told the Sun they were brought in to help with her campaign work and speech writing and urged Pitt to reduce the couple's support staff.
'Brad sees the women as a coven. He was furious at some of Arminka's decisions,' the source said.
The decisions are said to have included ditching Pitt's security team - some of whom had worked for the star for 20 years.
Lady Helic is seen as a key person on 'Team Angie' as the actress braces herself for the aftermath of her decision to divorce Pitt.
A source told Daily Mail's Alison Boshoff that Lady Helic is 'smart, strong, and impeccably loyal', adding that she is Angelina's 'assistant, adviser and best friend'.
Angelina watched Lady Helic be admitted to the House of Lords in 2014. They often travel together; recent trips include a visit to the International Criminal Court in the Netherlands and one to Burma at election time last summer.
Boshoff adds that the baroness's place in Jolie's inner circle is so central that she was with her when news of the divorce became public.