This is an archived article and the information in the article may be outdated. Please look at the time stamp on the story to see when it was last updated.

NEW YORK (CNN) — A New York City mother who has been enduring a living nightmare since October when her teenage autistic son disappeared has received ominous news.

Police notified the family of Avonte Oquendo, 14, on Thursday night that they found partial remains next to the East River in Queens as well as Air Jordan sneakers that match his shoe size, 5 1/2, dark jeans in the size he wore and underwear, the family’s attorney, David Perecman, said.

Perecman told CNN on Friday that Avonte’s mother is now preparing to provide investigators with her DNA so they can determine whether the remains are of her child.

Over months of searching for Avonte, his mother always held out hope. After he was missing for three weeks, she addressed reporters at an October 25 news conference.

“My thoughts are that my son is still out there and I want everyone to continue to help me search for my son,” she said. “He is not gone.”

The idea of her son wandering around New York City was terrifying because he cannot communicate verbally, she said soon after his disappearance.

“He has the mental capacity of a 7- or 8-year-old,” she said.

Her son was supposed to be with a one-on-one monitor at all times, Vanessa Fontaine explained.

But surveillance footage that captured her son on October 4 bounding out of Center Boulevard School in Long Island at 12:38 p.m did not show that he was with a supervisor.

“He doesn’t know that, you know, ‘I can get hurt in the street, someone can grab me and take me,'” his mother said. “He doesn’t know that. He doesn’t know fear.”

Authorities worked hard to find the teen.

They deployed sniffer dogs, combed surveillance footage, searched the sewer system, put up missing persons posters and filled the streets with fliers. There were alerts on the New York subway and messages in local newspapers. Divers using sonar to explore the city’s waterways.

“Obviously, we have devoted a tremendous amount of resources to the search,” Police Commissioner Ray Kelly told CNN affiliate WABC in late October. “Unfortunately, we are not hopeful that we’re going to find this young man alive, but we are continuing our search.”

Fontaine was not giving up hope and said she wanted police to try new methods.

“I don’t know what the commissioner was thinking of last night by saying that,” she said at the time. “But my son, he is alive, he is out there … it’s just that we are not looking in the right places.”

By Brian Vitagliano and Ashley Fantz

Download the fox4kc app to stay informed FOX 4 Android app | FOX 4 iPhone app