A physical fight broke out on Saturday during the Teen Mom 2 reunion taping in New York City, RadarOnline.com can confirm.
While filming the Unseen Moments special, DeJesus came out "ready to fight," a source told Radar, adding that the two immediately "started arguing."
In a shocking move, DeJesus' sister, Brittany, grabbed Lowry's hair and pulled her to the ground, the source claimed.
As the insanity continued, "all the cast, including host Dr. Drew, ran off stage."
Pregnant Chelsea Houska was "very upset" that she would get caught-up in the chaos, the source continued.
Fortunately, security intervened to break up the fight.
According to The Ashley, cast member Jo Rivera fled the set after the brawl and headed home because he was so disgusted with the drama.
The entire Teen Mom 2 family was present except Jenelle Evans. As Radar reported, the controversial star boycotted the reunion because MTV refused to pay for her fired husband David Eason to attend as well.
Outspoken Evans took to Twitter after hearing about the fight.
"So glad I stayed home from NYC this weekend with my babies," she wrote. "Too much drama! #CalledIt."
As Radar readers know, Lowry and DeJesus' bad blood began when the Teen Mom 2 newbie began dating the mother of three's ex-husband, Javi Marroquin.
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