(CNN) The man who was named as a person of interest in the gruesome killings of four men who were shot, dismembered and found in an Oklahoma river last week was taken into custody Tuesday in Florida on an unrelated charge, authorities said.
Joe Kennedy, 67, was arrested in Daytona Beach Shores in a vehicle that was reported stolen on Monday, Okmulgee Police said. He is being held on a charge of grand theft of a motor vehicle with no bond, according to the Volusia County inmate record.
"The District Attorney and the Sheriff will begin the process of getting Kennedy back to Okmulgee County," police said in a statement. "The murder investigation is ongoing and investigators continue to follow leads every day."
Police have not detailed why Kennedy is a person of interest and they have not named him a suspect in the murders.
According to the arrest warrant in Florida, he was reported as a missing person, but Kennedy advised police he was not a missing person and was not in any danger. He was transported to Volusia County Branch Jail, where jail records list him as being charged with grand theft of a motor vehicle and being a fugitive from justice.
He is also being held on a warrant issued for his arrest in Okmulgee County District Court in relation to a shooting in 2012. He is set to appear before a Volusia County judge on Wednesday afternoon, according to the clerk of courts.
It is unclear whether Kennedy has an attorney.
The arrest comes a week since four men -- Mark Chastain, 32; Billy Chastain, 30; Mike Sparks, 32; and Alex Stevens, 29 -- were reported missing after leaving Billy Chastain's home on bicycles around 9 p.m. on October 9, according to Police Chief Joe Prentice.
Their bodies, which had been shot and dismembered, were found days later in a river outside Okmulgee, a city of about 11,000 people roughly a 35-mile drive south of Tulsa.
"Although the official cause and manner of death is still pending, each victim suffered gunshot wounds," Prentice said. "All four bodies were dismembered before being placed in the river, and that is what caused difficulty in determining identities."
The remains were recovered over several days, and it's not clear what kind of evidence investigators will be able to recover.
"Whenever water is involved, it makes it much more difficult to identify evidence," the chief said.
Police have not recovered any bicycles, nor the gun used in the killings.
While it remains unclear exactly what led up to the men's deaths, it appears they were planning to commit a crime when they left Billy Chastain's home, Prentice said, citing a preliminary investigation.
The belief is based on "information supplied by a witness who reports they were invited to go with the men to quote, unquote, 'Hit a lick big enough for all of them,'" the chief said Monday in a news conference.
"That is common terminology for engaging in some type of criminal behavior, but we do not know what they were planning or where they planned to do it," Prentice added.
After the men were reported missing, police said they believed at least two of the men had cell phones with them. Investigators traced the phones' path, finding the devices went to two salvage yards -- one about 5 miles from the river, and the other about 10 to 12 miles from the river, Prentice told CNN on Saturday.
Police later found "evidence of a violent event" on property adjoining one of those locations, the chief said without elaborating.
The chief said police had a "person of interest" in the case Monday, describing them as someone "we'd like to talk to." However, the person had gone missing as of Saturday night and could be suicidal, Prentice said.
Now that the case is a murder probe, police will be more tight-lipped about further proceedings "to protect the integrity of the investigation," the chief said.
"I've worked over 80 murders in my career. I have worked murders involving multiple victims. I have worked dismemberments, but this case involves the highest number of victims, and it's a very violent event," Prentice said.
Jon Chastain, the uncle of Mark and Billy Chastain, told CNN their family was "shocked," "outraged," and filled with "heartbreak" when police announced the brothers, along with their two friends, were found murdered and dismembered.
"I'm a hard guy. People don't see me cry," Chastain said. "And I was devastated."
Chastain said he could not envision his nephews doing anything to warrant so much violence.
Mark was the father of two children, and Billy had four children. Chastain described them as hard workers and good fathers who loved their families.
"Whatever was going on, I don't know. But what I do know is we need some justice for this," Chastain said.
The families, he said, were already struggling financially before the deaths and have created a GoFundMe page to help cover funeral costs.