The Tulsa County Sheriff’s Office on Thursday said Mohawk Park security found the car that belongs to one of three people who are missing.   

It is part of an investigation the sheriff’s office is calling a “very unusual mystery.”  Two of the people missing were planning to go to Texas and a third disappeared while looking for them. 

Thursday morning, deputies were asking for the public's help to identify a person of interest. Since then, investigators said they found him and interviewed him, but are not releasing his name because he was not arrested. Tulsa County deputies spent part of the afternoon searching the Turley property where Jack Grimes lives. It is at least the second time they have been there, and the sheriff's office said this time, they were being more thorough. 

Hours earlier, the sheriff's office tracking team was using its bloodhound to search for clues at Mohawk Park, after park security recognized Grimes' car around 4:30 a.m. near the Oxley Nature Center. Deputies said Grimes and his friend, Dewayne Selby, were planning to go to a horse show in Fort Worth Friday but went missing.  

"Obviously this gives us cause for concern that they never departed on that trip. So at least that tells us that we need to focus our search right here in Tulsa County,” Casey Roebuck with the Tulsa County Sheriff’s Office said. 

Roebuck said Dewayne's mom, Glenda, who goes by "Cookie," is missing too. Roebuck said Glenda's car was found Tuesday on Highway 75 near 56th Street North. 

"Our ultimate goal, we want to find them alive, we want to find them safe. But we have very real concerns about their safety at this point,” Roebuck said. “The fact that their vehicles have been found and they're not with them. And if we can't find them OK then we want to build a solid case and bring those responsible to justice." 

Roebuck said Glenda was last seen Monday evening on surveillance video.  A family member said, "We are still praying that they are all three found safely." 

The family said Dewayne and his mom Glenda traveled to horse shows frequently and were very close. The sheriff's office said it wants to talk with people who go to Mohawk Park frequently and may have seen something around the time Grimes' car was left behind. 

"Did they see who dropped it off? Did they see anyone with it? So at least it gives us a piece of the puzzle to try to solve this very unusual mystery."

If you see any of the three missing people, call 911.