Former UFC star Phil Baroni was reportedly arrested for allegedly killing his girlfriend in Mexico over the weekend ... and the details are terrifying.
According to the Mexican outlet, Tribuna De La Bahia, police found Baroni's girlfriend naked and unresponsive in bed with a sheet covering her. The report says cops noticed bruises and markings all over her face and body ... and she showed no sign of life.
When authorities looked at Baroni's body, they reportedly noticed his hands were red. They took photographs.
The 46-year-old -- who was reportedly under the influence of drugs and alcohol -- reportedly claimed the woman couldn't get out of the tub by herself, so he assisted. She then complained of being cold, so Baroni said he took her to bed, removed her clothes and wrapped her in a blanket.
Baroni then says he went out for cigarettes and beer, per her request.
When he got back, Baroni reportedly told authorities he believed the woman was asleep. Tragically, she was deceased.
Authorities are planning to conduct an autopsy on the alleged victim to determine her cause of death.
Baroni was arrested for murder ... and is currently behind bars.