UFC bantamweight Irwin Rivera was arrested Thursday and charged with two counts of attempted murder, according to an incident report obtained by ESPN's Marc Raimondi.
Boynton Beach Police in Florida reportedly arrested Rivera, who's being held without bail.
A police spokesperson said Rivera is accused of stabbing his two sisters, Raimondi adds.
Officers were called to a residence and found two women suffering from multiple stab wounds, according to the incident report.
One of the sisters said she woke up to the bantamweight fighter stabbing her with a knife while in a spare room of his home. Both sisters were rushed to the hospital, and their current conditions are unknown.
Rivera reportedly fled the scene, but police managed to make contact with the 31-year-old at around 7 a.m. ET on Thursday.
"I killed my sisters," he reportedly told officers, adding that he stabbed his siblings with a brass-knuckle knife after being told by "a higher power" to do so.
The UFC issued a statement saying it's investigating the "extremely troubling" situation.
"UFC is aware of the recent incident involving Irwin Rivera and subsequently received information from his management that he has been exhibiting behavior consistent with mental health issues," the statement read. "The allegations are extremely troubling and the organization is currently gathering additional information. The investigation is ongoing and any potential next steps including disciplinary action or medical attention will be determined upon the conclusion. Furthermore, UFC has informed Rivera's management that he will not be offered a bout at this time."