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Violent Crime Task Force Joins Search For Four Oklahoma Men Who Mysteriously Disappeared

Brothers Mark and Billy Chastain, Mike Sparks and Alex Stevens have all been reported missing. They were last seen on their bicycles near Billy's home on Sunday evening. 

By Jax Miller
Police handouts of Billy and Mark Chastain

Law enforcement officials in Oklahoma are searching for four men who mysteriously vanished over the weekend.

The four friends were last seen on their bicycles on Sunday at around 8:00 p.m. in Okmulgee — about 40 miles south of Tulsa — and never returned to their homes, according to the Okmulgee Police Department.

Mark Chastain, 32, Billy Chastain, 30, and Mike Sparks, 32, were all reported missing Sunday by Mark’s wife. According to CBS Tulsa affiliate KOTV-DT, Mark and Billy are brothers.

Hours later, the mother of Alex Stevens, 29, also reported her son missing.

Okmulgee police say they believe the men left Billy Chastain’s home on their bicycles. But, despite numerous — albeit unconfirmed — sightings of them around the town, neither the men nor their bikes have been found.

Police say that, although there is no sign pointing to foul play, they’ve enlisted the help of violent crime investigators, according to the release.

Police handouts of Billy and Mark Chastain

“Although there is no evidence to indicate violence or any foul play at this point, a small contingent from the District 25 Violent Crime Task Force is assisting, which allows us to bring more resources to bear in the search,” stated police.

Two from the group are believed to be in possession of their mobile phones, though multiple calls went straight to voicemail. However, police were able to track Mark Chastain’s phone in an area south of Okmulgee, “but it was turned off or lost power” after that, said police.

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Investigators tracked the phone’s ping to a junkyard off Highway 75, according to KJRH-TV.

Subsequent searches for the men around that area were fruitless.

Okmulgee Police Chief Joe Prentice released an update Wednesday evening.

“Task Force investigators are shot. These men are exhausted,” Prentice stated. “We will start fresh tomorrow unless something time-sensitive comes in overnight.”

Police handouts of Alex Stevens and Mike Sparks

Investigators have spent much of the investigation tracking down possible sightings, including a report of Stevens alone at a south-side smoke shop at around 4:00 p.m. on Sunday. Another witness reported seeing the Chastain brothers near the YMCA on Monday morning.

On Thursday, Chief Prentice addressed these — and other — potential sightings.

“We were unable to confirm any reported sightings,” Prentice stated. “An interview was conducted today regarding a report that a citizen observed all four men walking down the street around 2:00 a.m. on Tuesday morning. This also cannot be confirmed with independent witnesses or video.”

Police say they’ve issued search warrants for phone records and Facebook accounts.

They also intend to sift through “hours” of recently-obtained GPS data and video, which police say will be a “long and tedious process.” However, they reminded the community that such data might only prove the locations of the men’s phones and not necessarily the location of the men themselves.

Mark Chastain’s wife, Jessica Chastain, told KJRH the four friends often hung around the home and that “they don’t go far. Never.”

“If they’re alive, someone’s holding them hostage or something,” Jessica Chastain said. “But I don’t see four grown men being held hostage by one person.”

She told KOTV-DT that her husband — with whom she shares two children — had plans for the day after he disappeared.

“Mark was supposed to be home Monday to watch our daughter because I started a new job,” she explained. “And Mark would never, never. He’s always there for us. Always.”

Mike Sparks’ fiancée, Chrystal Parker, also told KJRH-TV she tried calling him 197 times to no avail.

“I don’t want to think the worst,” she told KOTV-DT. “I have hope.”

Anyone with information is urged to contact the Okmulgee Police Department at 1-918-756-3511.