Pierce Crowley, 15, of Rye, N.Y. was found just after midnight Wednesday night.

A teenager who vanished last Friday from Westchester County, N.Y., has been found safe in Manhattan, officials said Thursday.

Police said officers spotted Pierce Crowley, 15, just after midnight Wednesday night with a group of other teenagers in Washington Heights, in the northern part of New York City. They questioned Crowley, and once they determined it was the teen, officers returned him to his family's house in Rye.

"He was unharmed, appeared to be in good health and good spirits," White Plains Police Lt. Eric Fischer told msnbc.com.

Police, family members, and hundreds of volunteers had been searching for Crowley, plastering fliers around Manhattan, Westchester and the Bronx. On the day he vanished, he had been at White Plains' New York-Presbyterian Hospital in what his parents described in an email to friends as "a fragile state."

He hadn't been feeling well when he disappeared, his parents had said, but didn't elaborate. The medical center where he was last seen is one of the top psychiatric hospitals in the nation.

According to police, a friend of Crowley's had come forward to say the two left the hospital and went to The Cheesecake Factory restaurant together, Newsday reported.

They then took a cab to the White Plains Metro-North train station, the report said. Crowley's friend took a train to New York City while Crowley stayed behind in the cab.

Crowley had $40 in his pocket, no credit card and no cell phone, police told Newsday.

Previous report: Teen missing; parents say he was in a 'fragile state'

"We were treating it as a missing persons case. At no time did we ever have any information that foul play was suspected," Fischer told msnbc.com.

On Thursday morning, a Facebook page called "Find Pierce Crowley," which had garnered nearly 7,000 fans, was updated with a single sentence: "Pierce is safe back home, thank you for all your help!"

Crowley's parents did not return a phone call from msnbc.com, but his mother, Gretchen, told Newsday, "We're just so incredibly relieved, I can't even put it into words. He's here and he's safe and obviously everybody is thrilled here."

He was happy to back with his family, a White Plains public safety commissioner said.

"He looks like he just walked out and decided to have an adventure," David Chong told Newsday. "It's like finding the proverbial needle in the haystack."

Tips about Crowley's location, including one Wednesday night about him being in the Washington Heights area, had poured in throughout the investigation, the White Plains police said.

Crowley is a student at Iona Preparatory School in New Rochelle, where he plays hockey and lacrosse and runs cross-country, Newsday said.

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Courtesy of the Crowley family

Missing 15-year-old Pierce Crowley.

A teenager from Westchester County, N.Y., has been missing since last Friday and was "in a fragile state" when he was last seen, his concerned parents said.

Police say Pierce Crowley, 15, of Rye, N.Y., left New York-Presbyterian Hospital in White Plains, N.Y. with a close friend before he went missing.

In an email to friends, his parents wrote that their son was “in a fragile state” and hadn't been feeling well when he disappeared. "It is URGENT that we locate him ASAP," they wrote, according to the New York's Hudson Valley Journal News.

It's not clear what Crowley was in the hospital for. The White Plains medical center is one of the top psychiatric hospitals in the nation.

According to police, Crowley's friend came forward to say the two left the hospital and went to The Cheesecake Factory restaurant together, Newsday reported.

The two then took a cab to the White Plains Metro-North train station, the report said. Crowley's friend took a train to New York City while Crowley stayed behind in the cab.

According to White Plains police, Crowley was last seen wearing a bright blue Florida Gators short sleeve T-shirt with dark blue jeans and black sneakers with lime green-trim. The teen is enrolled at Iona Prep in New Rochelle.

Crowley has light brown hair, blue eyes, and wears braces, The Journal News said. He is 5'10'' and 150 pounds.

Hundreds of volunteers have mobilized to help the Crowleys find their son, a family friend told media. Fliers were posted in Westchester, Manhattan and the Bronx, and the family set up a Facebook page. 

“We love Pierce. We miss Pierce,” his father, Peter Crowley, said, according to Newsday. “His brothers miss Pierce. We need him home.”

Crowley family friend Peggy Dunne told The Journal News, “(Pierce) is a charming, talented, bright student and an amazing athlete. His family and his friends are just totally distraught about him missing.”

There is a reward for information that leads to his safe return, the family said. White Plains police have asked anyone with tips to contact them.

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