Police have arrested a man caught with a car stolen from a Florida home where a couple and their son were found dead. Their daughter — the man's wife — remains missing.

Police in Tarpon Springs, Florida, identified the suspect Friday as 25-year-old Shelby John Nealy. He was taken into custody in the Cleveland suburb of Lakewood, Ohio. Authorities said he was initially charged with receiving stolen property because he was driving one victim's car. It wasn't immediately clear if he has a lawyer.

Investigators identified the victims as 71-year-old Richard Louis Ivancic; his wife, 59-year-old Laura Ann Ivancic; and their son, 25-year-old Nicholas James Ivancic. Nealy's wife, their 21-year-old daughter, Jamie Nicole Ivancic, is missing under what police called "suspicious circumstances," without elaborating.

"We do fear she, too, may be a victim of foul play," said police Maj. Jeff Young said at a news conference Friday in Tarpon Springs. "This is an ongoing investigation."

Authorities making a welfare check on New Year's Day said they found the bodies in a state of "advanced decomposition." Police have not said how they died but that the killings likely happened Dec. 19 or Dec. 20. The bodies of three small dogs also were inside the home.

Tarpon Springs police investigators have interviewed Nealy — who also goes by the name Shelby Svenson — in Ohio and they say he admitted involvement in the killings.

Nealy was arrested after authorities were able to track a red 2013 Kia Sorento owned by Laura Ivancic to Ohio. He was taken into custody after walking outside toward the vehicle from an apartment, where the younger couple's two children aged 2 and 3 were inside unharmed. They were taken to a family services agency.