A young Brazilian fighter died today just prior to weigh-ins for his Shooto Brazil 43 bout, according to the event’s organizer.

Andre Pederneiras, Shooto’s president and a veteran trainer/manager, today confirmed the news of Leandro “Feijao” Souza’s passing with MMAjunkie.com.

As he wrote on Facebook (translated from Portuguese by MMAjunkie.com): “It’s with a heavy heart that through this letter we share the news of the passing of the athlete Leandro Caetano de Souza. The athlete passed away at the emergency unit in Botafogo. The reasons are not yet known to us. We would like to express our condolences to all friends and family.”

Souza (5-5), a 26-year-old who represents the mighty Nova Uniao gym, was slated to fight Gabriel Brasil (1-1) in a flyweight bout at Friday’s event in Rio de Janeiro. The weigh-ins took place in the same city.

Few other details were immediately available, but Souza’s teammate, Andre Santos, told MMAFighting.com that the fighter passed out just prior to official weigh-ins. He was trying to cut two remaining pounds, according to MMAFighting.com’s Guilherme Cruz.

Santos said Souza’s death “is related to his weight cut,” according to MMAFighting.com However, he told MMAFighting.com he wasn’t actually on site for the weight-cutting process.