(Fremont County, WY) – 40-year-old Anthony Ray Sullivan was detained north of Riverton on July 4 after he was reported to have killed his girlfriend in Billings, MT, and later requested to be turned over to law enforcement, according to a release issued by the Fremont County Sheriff’s Office today, July 7.
He was subsequently served an arrest warrant while in the Fremont County Detention Center.
“On July 4, 2025 at around 3:21 pm, the FCSO received a 911 call indicating that a male subject was in a pullout off of Wyoming Highway 789 north of Riverton, stating that he had killed his girlfriend,” the FCSO release states.
“The 911 caller told Deputies that they had stopped their RV in the pullout to take a rest from traveling,” the release later informed. “When they exited the RV a short time later, they encountered Sullivan (lying) on the ground in front of their RV, stating that he had killed his girlfriend and asking for them to call 911.”
After deputies later made contact with Sullivan and he confirmed what the caller had told dispatch, FCSO Communications then contacted the Billings Police Department and confirmed that Sullivan was a suspect in a homicide that was under investigation in Billings.
Sullivan was then detained and later transported to the Detention Center by a Wyoming Highway Patrol unit, where he ultimately received the warrant for his arrest.