Jenelle Evans and Nathan Griffith went to war during filming on the Teen Mom 2 season eight reunion.

Following this past weekend's filming session in Los Angeles, an insider is speaking out.

“When it was time to leave that night Nathan was letting Kaiser say bye to Jenelle and her mother Barbara,” a source told Radar Online on October 24. “Barb gave Nathan a hug goodbye and then gave Ashley a hug goodbye and said, ‘Have a safe trip back.’ That’s when Jenelle screamed, ‘I thought the f**king b***h said she wasn’t going to film.”

Then, when Lanhardt told the mother of three she wouldn’t’ be filming, Evans “started screaming at her saying Ashley hasn’t even f**king met her yet.”

At that point, Lanhardt attempted to formally introduce herself to Evans by holding out her hand. Unfortunately, Evans didn’t take kindly to the gesture and their argument escalated.

“Bodyguards and camera crew were all over the place and in between them,” the insider said. “She was screaming at Nathan and Ashley like a lunatic. Ashely turned in the opposite direction and walked back towards the green room.”

As Griffith attempted to lead his girlfriend into his room, Evans reportedly tried to fight her and was screaming at Lanhardt as they walked away.

“Jenelle Evans tried to fight her way into their room and was still screaming at Ashley,” the insider continued. “Nathan then pulled out a drug test and told [Jenelle and David] to take it. At that point, both of them walked away.”

From there, Evans and her husband ventured to the room of Evans’ mother, Barbara, and proceeded to attack her for hugging Griffith and Lanhardt.

“That’s when Barbara lost it and was hysterical crying an yelling at them,” the source revealed. “David and Jenelle were attacking her back.”

According to Evans herself, she told a very different story on Instagram live just a short time after the rumors regarding her fight.

“Ashley didn’t say anything to me the entire time. She didn’t introduce herself to me,” Evans said. “I was like, ‘Well damn, you just hugged my mom.’ I was a little bit upset about that. The argument started when we were leaving backstage.”