A 20-year-old man from Bucks County, Pennsylvania, admitted his involvement in the murders of four missing young men from the area, his lawyer said Thursday. Cosmo DiNardo confessed to his “participation or commission in the murders of the four young men” and told police where their bodies could be found.

DiNardo did not say whether he had killed the four men himself, according to his attorney Paul Lang. In exchange for the confession, prosecutors in the case said they would not seek the death penalty for DiNardo, Lang said.

Read: Texts From Cosmo DiNardo About 4 Missing Men Show Lack Of Concern

Jimi Patrick, 19, Tom Meo, 21, Mark Sturgis, 22, and Dean Finocchiaro, 19, were all seen for the last time at differing times last week. DiNardo was arrested Wednesday as a “person of interest” in the case after he was caught stealing and attempting to sell the car of one of the missing men.

The remains of at least one of the men were found after an extensive search on a massive property belonging to DiNardo’s parents. They were identified as that of Finocchiaro, though investigators said they were working to identify the rest of the remains.

A man who requested anonymity told the Philadelphia Inquirer Thursday that DiNardo had spoken of murder in the past.

“He’s told me and my friends, ‘Yeah, I’ve killed people before, I just haven’t been caught,” the man said. “We literally were just like, ‘Yeah, all right, Cosmo, sure you did.’ No one actually thinks someone’s capable of this.”

DiNardo had contact with police more than 30 times since 2011, a law enforcement source told ABC News. Residents from the area said that following an ATV accident that took place about seven months ago, something became “off” with DiNardo.

It remained unclear exactly how DiNardo knew the four men. Eric Beitz, a friend of one of the missing men, told the Philadelphia Inquirer that DiNardo was “aggressively” seeking new customers to sell marijuana and guns to and that some of the men first met DiNardo while he was trying to sell them weed.

Upon his arrest as a person of interest, prosecutors said DiNardo was schizophrenic and a flight risk. His lawyers, however, said his mental illness was being exploited in the case. Text messages shared by an unidentified source involved in a conversation with DiNardo on the app Snapchat revealed the 20-year-old’s apparent lack of concern for the missing boys.

“Cosmo isn’t your buddy Dean missing,” one person in the group message obtained by the Inquirer asked. “Aren’t you worried about buddydead [sic] dean?”

“I mean, I know the kid,” Cosmo answered. “But yeah I feel bad for his parents. He’s a pill popping junky who had 2 duis… He prob just jumped parole Or probation.”

Read: Case Of 4 Missing Pennsylvania Men Has 'Mind-Boggling' Scope, Authorities Say

DiNardo’s family owned multiple properties, including the farm on which the human remains were found, worth millions. The 68-acre farm cost $5.4 million in 2005, according to NBC News. The family reportedly made their fortune in trucking and concrete.

“As parents, Mr. and Mrs. DiNardo sympathize with the parents and families of the missing young men,” attorney Fortunato Perri Jr. said in a statement earlier this week. “They are cooperating in every way possible with the investigation being conducted by law enforcement.”