NEW YORK (AP) — A man stabbed his mother to death and cut up her body, which was found in pieces in a series of trash bags on city streets, authorities said Wednesday.

Police added a murder charge against Bashid McLean, 23, hours after he and an acquaintance, William Harris, 26, were first arrested on charges of unlawfully dissecting a human body and hindering prosecution. Each man initially implicated the other in Tanya Byrd's killing, according to accounts they gave authorities.

It was unclear whether McLean, whose family described him as a troubled man who had long harbored anger toward his mother, or Harris had a lawyer. No phone numbers could be found for their homes.

Meanwhile, the medical examiners determined Wednesday that Byrd died from being stabbed in the neck. The medical examiner's office officially ruled her death a homicide in the chilling case, which came to light when a resident's dog sniffed out one of the bags early Tuesday on a Bronx street.

Byrd, a 45-year-old home health aide, was last seen alive Monday. Her remains were stuffed in four bags and scattered along four blocks, police said.

The resident's dog found the first bag — a heavy-duty plastic garbage bag stuffed in a duffel bag, with the woman's bloodied leg inside — in a trash pile in the Melrose neighborhood.

Police then found the three other bags and their macabre contents, including the victim's head, part of her torso and other limbs.

Witnesses told police an SUV dropped the bags off Monday night or early Tuesday.

Friends described Byrd as upbeat and generous.

"Anything you would have needed, she would have given it to you," friend Elizabeth Cruz told WCBS-TV.

McLean had a history of psychiatric problems and animus toward his mother, relatives told local media.

"He did destructive things," his father, James McLean, told the Daily News. "He set fires. Nobody could control him."

While the case and its discovery were particularly gruesome, there have been similar episodes in the city in recent years.

In one bizarre case, a passer-by found a woman's body in a suitcase while rummaging through trash in East Harlem in December 2010. Police, after releasing surveillance video of a man wheeling the suitcase down a sidewalk in the area, arrested Hassan Malik.

He ultimately told detectives he got into an argument with the woman, Betty Williams, choked her with an electric cord, packed her in the luggage and abandoned it in a street, according to a court document.

Malik, 57, is serving a 20-year prison sentence after pleading guilty to manslaughter.

In another case, a teenage girl's body was found wrapped in garbage bags in a Bronx alley in September 2009. The girl, Jamia Hazel, had been stabbed to death.

A man, Darrell Spencer, is awaiting trial on murder and other charges in her death. He has pleaded not guilty.

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