SOLEBURY TOWNSHIP, Pa. (CBSNewYork/CBS Philly/AP) — A person of interest in connection to four men missing in Bucks County, Pennsylvania since last week is back in custody Wednesday.

20-year-old Cosmo DiNardo, linked to a Pennsylvania farm at the center of a search for the missing men, tried to sell one of the men’s car after he went missing, even as it contained the man’s “life-saving” diabetic kit, authorities announced Wednesday.

Officials in Bucks County, Pa. provide update on the investigation Wednesday:

Tom Meo, 21, never went anywhere without the medicine, a prosecutor said as the search intensified. Meo and two others were last seen in suburban Philadelphia on Friday, while the fourth vanished two days earlier.

Authorities Name Person Of Interest In Search For Missing Men In Bucks County, Pennsylvania

DiNardo, described as a person of interest, was taken back into custody Wednesday on a stolen vehicle charge, less than a day after his father posted 10 percent of the $1 million bail set when the son was arrested Monday over an old gun charge. His parents own the sprawling farm property the FBI and police cadets have been methodically searching for four days.

“The search at the scene is really intensifying,” Bucks County District Attorney Matthew Weintraub said at an afternoon news conference. “I’m very encouraged … that we’re going to get some finality in this just prolonged ordeal.”

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Weintraub plans to ask the judge to set a full-cash bail on the stolen car charge, calling DiNardo an even greater flight risk now. He has said the search for the missing men could be “a marathon” given the task at hand.

Police have recovered what he called “important” evidence but no human remains during a massive four-day search of locations across the county.

The DiNardo farm alone covers 90 acres, much of it cornfields. They also own other nearby farm parcels, along with concrete and construction businesses based in Bensalem, about 20 miles (32 kilometers) away, where the son was arrested at the family home.

The FBI has been using heavy equipment to dig a deep ditch on the farm property, then sifting through each bucket of dirt by hand.

“We’re going to continue digging and searching that property until we’re satisfied that they are not there,” Weintraub said earlier in the day. “This is just really, really rough on everybody involved because of the heat, the magnitude, the scope — and the stakes are incredibly high, life and death.”

At least some of the missing men are friends, but it’s unclear how well they knew DiNardo, if at all. Online records suggest he was a year ahead of another missing man, 19-year-old Jimi Tar Patrick, at a Catholic high school for boys in Bensalem.

bucks county missing men Person Of Interest In Search For Missing Men In Suburban Philadelphia Back In Custody

Four young men went missing last week in Bucks County, Pennsylvania. Authorities named a person of interest Tuesday. (credit: KYW)

The others missing are 22-year-old Mark Sturgis and 19-year-old Dean Finocchiaro. Sturgis and Meo worked together doing construction for Sturgis’ father, while Finocchiaro was a mutual friend.

DiNardo was arrested Monday on a gun charge that had been dismissed this spring. He is accused of possessing a shotgun and ammunition despite a previous mental health commitment.

DiNardo’s social media posts suggest an avid interest in hunting, fishing and Air Jordan sneakers, which he appeared to sell online. He had enrolled in a nearby college at one point as a commuter student, with hopes of studying abroad in Italy, according to an article on the college website. He had a few other brushes with the law since turning 18 over traffic violations and other minor infractions.

Neither DiNardo’s parents nor his lawyer have commented this week, and Dinardo is

currently being held on $5 million bail — charged with receiving stolen property, CBS 3’s Joe Holden reports.

The farmland being searched is in the town of Solebury, about 30 miles north of Philadelphia.

If you have any information on the men’s disappearance, you’re asked to call Solebury Township Police at 215-297-8201.

(© Copyright 2017 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)

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