He was the focus of a nationwide manhunt, and police caught him in North Carolina. He was returned to Winchester police headquarters Tuesday night.
When he stepped out of the police van, he made an interesting statement.
He apologized to his mother and her two cats, and then he admitted to FOX 25's Bob Ward that he murdered his mother.
Here is how it went down.
"To my mother, Barbara McAveeney, and to her two cats, Pumpkin and Puffy McAveeney, I deeply apologize. Sometimes I get out of control," Matthew McAveeney said.
"Did you do it?" Bob Ward asked.
"Yes," McAveeney replied.
"What did you do? What did you do to her?" Ward asked.
"I murdered her," McAveeney admitted.
Neighbors asked for a wellness check after they detected an overwhelming odor coming from her apartment.
Matthew McAveeney, who lived in the condo at least part time, disappeared.
The Middlesex County District Attorney released surveillance photos of McAveeney taken at around the time Barbara McAveeney was last seen alive.
Days later, Matthew McAveeney was arrested hundreds of miles away in a Walmart parking lot in Belmont, N.C.
Authorities say he got into a scuffle with police and resisted arrest.
Matthew McAveeney is facing a series of charges including assault with intent to murder and two counts of animal cruelty.
He spent the night at the Winchester Police Department, and was scheduled to be arraigned at 9 a.m. in Woburn District Court.
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