NEW YORK — When Paula Chin, a 65-year-old Tribeca mother and businesswoman, was reported missing Monday, New York City police reached out to the public for help.

“Known to wear a white flowered nightgown and a purple grey jacket,” the Missing Persons Squad said on Twitter.

But by Tuesday, Chin’s body had been found stuffed in a garbage bag outside her family’s weekend home in Morristown, New Jersey. Her throat had been slashed. By Wednesday, her son, Jared Eng, 22, had been arrested and charged with concealing her body, with the help of his girlfriend and a friend.

Though Eng had not been charged with his mother’s killing, he was the prime suspect, New York police said. Detectives believed the motive for her murder was financial.

As he was led out of a Manhattan police precinct Wednesday after questioning, Eng was asked by reporters if he had killed his mother. “I did not,” he said. “I loved her. She gave me everything.”

Chin’s body made the trip Thursday afternoon from Morris County to the Manhattan medical examiner’s office, where doctors determined she died from “multiple blunt impacts” to her head and a “stab wound” to her neck.

It was a shocking turn of events for a Manhattan family that had seemed prosperous and stable. Eng attended the selective Brooklyn Technical High School and went on to study at SUNY New Paltz, according to his Facebook page.

Chin’s Facebook profile shows her smiling at a Tribeca charity gala and posing with her two sons, Jared and Brandon, 25, at Zion National Park in 2018. The boys’ father, Philip Eng, died 10 years ago, public records showed.

Jared Eng was formally charged Thursday morning in Manhattan Criminal Court with tampering with evidence and concealment of a corpse, along with his girlfriend, Caitlyn O’Rourke, 21, of Patterson, New York, and a second friend, Jennifer Lopez, 18, of Manhattan.

Eng was ordered held without bail. O’Rourke was held on $50,000 bail, and Lopez’s bail was set at $100,000. Like Eng, O’Rourke was a student at SUNY New Paltz, according to her Facebook page.

“The case is in its early stages and will ultimately be resolved in the courtroom, not in the media,” Eng’s lawyer, Joel Cohen, said.

A criminal complaint described in grisly detail how Eng and Lopez allegedly transported Chin’s remains to New Jersey on Jan. 31 in Chin’s own car, a 2004 Toyota Land Cruiser.

Security camera videos reviewed by police showed a woman resembling Lopez backing up the car in front of Chin’s apartment building early on Jan. 31, the complaint said. Then someone resembling Eng put a large duffle bag in the trunk at 2:31 a.m.

When police searched the car, they found blood on the carpet and a blanket, clothing and duct tape, the criminal complaint said.

O’Rourke, the police complaint said, told detectives in an interview that Eng called her after he and Lopez had moved the body. She said Eng admitted to her that he had killed his mother, telling her it had taken her “a while to die.”

“It’s all clean, the hardest part was backing up the car,” said a text message between Lopez and O’Rourke, according to the complaint.

O’Rourke told police that on Feb. 1 the three friends went together to Chin’s second home, on Bailey Hollow Road in Morristown, and moved Chin’s body to an outside garbage container on the property. O’Rourke also said she attempted to wash clothing from the crime scene in the washing machine at the home.

Police said they found bloody rubber gloves in the garbage and bloodstains on the New Jersey residence’s garage floor. More bloody gloves, along with blood traces, were found inside the Manhattan apartment, the complaint said.

Eng’s older brother, Brandon, had reported her missing to police Monday.

Chin’s Tribeca building, sandwiched between converted lofts on Vestry Street, was quiet Thursday morning. The first floor is a commercial space with a large garage door, and the upper two residential floors — including the third, where Chin had lived with her family — were empty, a police officer at the scene said.

City property records showed that Chin had bought the building at 17 Vestry St. in 1987 with her late husband. They had also owned the Morristown home, which was on a winding mountain road.

“Whenever she was out here, she was very pleasant to us,” said Tracey Abbott, her neighbor in Morristown. “She always had a big smile and seemed like a very nice person.”

Another Morristown neighbor, Ann Vanella, said, “To have died the way she did, is shocking. It is a very sad situation, and it is hard to believe.”

Chrissie Williams, a spokeswoman for SUNY New Paltz, said Eng had started studying at the university in 2015, but had not enrolled in classes this semester.

On Instagram, Eng described himself as a “creative consultant, media enthusiast, gamer” and “cat dad.” In May, he posted a picture of himself smiling with his mother at the Frying Pan restaurant on the Hudson River.

Eng’s most recent Facebook profile picture shows him posing with a camera. “I’m an adult now?” he captioned the photo.

“City kid stretching his wings,” he wrote as his Facebook introduction. “But first, he must prune his broken feathers.”

This article originally appeared in The New York Times.