Mayhem broke out at the BJJ Stars event in Sao Paulo, Brazil, this weekend. The incident went down during the main event between Felipe Pena and Erberth Santos.

It is reported that the brawl started after Santos seemingly hurt his knee from a sweep attempt by Pena. As officials assessed his injury, Santos started arguing with someone in the crowd. Reports claim that Pena’s team were taunting Santos for faking the injury. Although the way Santos reacted, Pena’s team may have had a point.

Santos charged into the crowd and all mayhem broke out. As you can see in the videos below.

BJJ Stars promoter Fernando Lopes spoke to MMA Fighting about the incident.

“He was provoked by someone in the crowd, who was cheering for Felipe or against him. I’m a black belt for 21 years and an athlete has to be a black belt on and off the mat to deserve a black belt in my team. I wouldn’t give a blue belt to an irresponsible man who fights in the street.”

“The event was great, getting a lot of praise, and it’s a shame that one person’s attitude can tarnish the entire work of many people in the end. I know how hard my partners and I worked, I left many things aside to put my passion in first place, and that can’t tarnish all the work we’ve done.”

The incident marred what was otherwise a fantastic night of BJJ action.