Simone Biles says her "heart aches" for everyone involved in the horrific triple murder that her brother allegedly committed -- saying, "There is nothing that I can say that will heal anyone's pain."
The Team USA gymnastics superstar's brother, Tevin Biles-Thomas, is facing murder charges for the Dec. 31 shooting in Cleveland, which left 3 dead.
Cops say the shooting broke out during a fight at a house party at an Airbnb rental in Cleveland -- and say they have identified 24-year-old Biles-Thomas as the shooter. After an investigation, he was arrested on Friday.
Simone -- the 5-time Olympic medalist -- finally spoke out about the situation late Monday night ... saying, "My heart aches for everyone involved, especially for the victims and their families."
"There is nothing that I can say that will heal anyone's pain, but I do want to express my sincere condolences to everyone affected by this terrible tragedy."
"I ask everyone to please respect my family's privacy as we deal with our pain. XO."
She added, "Still having a hard time processing last weeks news."
Biles-Thomas is facing a slew of charges -- including 6 counts of murder, 3 counts of voluntary manslaughter 5 counts of felony assault and 1 count of perjury. He's scheduled to be arraigned on September 13 in Ohio.