TULSA, Okla. (KTUL) — Three people are still missing tonight from the Turley area.
It's now been a week since 59-year-old Dwayne Selby and 76-year-old Jack Grimes have been seen or heard from.
Selby's mother, 80-year-old Glenda "Cookie" Parton, also has been missing since Monday.
Tulsa County Sheriff's Office Director of Communications, Casey Roebuck, said investigators are continuing to vet tips, interview folks and search.
"A week is a very long time for there to be no word from Jack or Dwayne," Roebuck said, "So to say we're growing increasingly concerned would be an understatement."
According to the Sheriff's Office, Grimes's Silver Alert was issued because he's diabetic and needs insulin to manage his health.
Parton also has a medical condition.
"So far we still don't have any definitive answers. Multiple theories that we're working on but so far, no one has been ruled out, no motive has been ruled out," Roebuck said. "We're still open to all possibilities in this case as to what happened to these three people and who may be responsible for it."
Since the start of the week, the Sheriff's Office has located Parton's car on Hwy 75 near the 56 Street N exit.
Carol Selby, relative of Dwayne and Parton, said it was odd.
"To me, if someone left the keys in her car just sitting on the highway, that's just suspicious," Carol Selby said.
The car Dwayne Selby and Jack Grimes should've taken to a horse show in Fort Worth was also found in Mohawk Park.
Carol Selby told NewsChannel 8 Selby and Grimes had traveled to horse shows together, "hundreds of times."
"They have been companions for 19 years," Carol Selby said. "They go to Colorado, they go to Texas, they go to Texas a lot, I know they've been to Tennessee. They go to a lot of places."
With the cars now found, it allows investigators to narrow the search.
"So that told us we need to concentrate here in Tulsa County," Roebuck said. "Keep looking for evidence and leads here. Which actually is very helpful. It is a big piece of the puzzle."