Grandmother and adult son 'kill themselves and three young children' by pumping car full of carbon monoxide after bitter custody battle

A grandmother, along with her grown son, has committed suicide and killed her three young grandchildren in Ohio by suffocating them with carbon monoxide.

Sandy Ford, 54, was about to lose custody of her three grandchildren, Paige Hayes, 10, Logan Hayes, 6, and Madalyn Hayes, 5.

Authorities believe she and her son Andy Ford, 32, who was the children's uncle, may have killed them at their home in Toledo, Ohio, to prevent Sandy's daughter from regaining custody.

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Tragic: This is the Dodge pickup truck that was found running in the locked garage with a hose running to a Honda Civic where five bodies were found

Firefighters broke into a garage to find a Dodge pickup truck running with a hose running to a Honda Civic where the five bodies were found

Firefighters found a truck with the engine running and hoses leading from the exhaust into a Honda Civic in the family's garage on Monday night.

The three children, as well as Sandy and Andy Ford and the family's two dogs and a cat were all found dead inside the car.

Sandy Ford's husband, Randy, called police Monday afternoon to say that he had returned home and found suspicious notes in the house from his wife, son and grandkids. He said he wasn't able to enter the garage.

Firefighters used a sledgehammer to open a door to the garage, which had been barricaded shut.

Investigators believe they died of carbon monoxide poisoning. The five victims lived with Randy Ford in the house in a residential neighborhood close to the Michigan state line.

Horror: Police believe a custody dispute may have been the motive in the apparent murder-suicide

Ohio firefighters had to use sledgehammers to force open the barricaded garage door

Sgt. Joe Heffernan said Sandy Ford had primarily taken care of the children at her home for the last four years, but their parents - the Fords' daughter, Mandy Hayes, and the children's father, Chris Hayes, were trying to regain full custody of them.

He said Sandy Ford was upset about that, and he believes that was the motive for the murder-suicide.

Doug Hall, a neighbor who lives across the street, said he saw the Fords' son and the children raking leaves last week. He said the only unusual thing he's noticed was a police car at the house last Thursday. He said he didn't know why it was there.

Another neighbor said he saw the kids helping with the yard work and playing in the leaves just a few days ago.

'One minute they're doing the leaves, and then the next there are cop cars all over,' Eric Pieper said.

VIDEO: Police suspect murder-suicide in the death of five family members