In a new development in the search for four missing men in Bucks County, Pennsylvania, police found the body of one of the missing men early Thursday. Bucks County district attorney Matthew Weintraub identified the deceased man as 19-year-old Dean Finocchiaro. The police also discovered human remains that are yet to be investigated. 

"We are not done yet. This is a homicide, make no mistake about it," Weintraub told reporters in a news conference, according to CNN. Authorities said the body was discovered by cadaver dogs from a 12-feet-deep "common grave" on a farm in Solebury Township, about 30 miles north of Philadelphia.

The search of the property, owned by Antonio and Sandra DiNardo, was conducted after their 20-year-old son Cosmo DiNardo was arrested Wednesday in suspicion of stealing and attempting to sell a car owned by one of the missing men. Authorities also received tips saying DiNardo was seen with the men before they went missing.

Read: Police Suspect Foul Play After 4 Young Men Go Missing In Pennsylvania In A Single Week

DiNardo, who is a person of interest in the case, was previously taken into custody on an unrelated gun charge, authorities said. The 1996 Nissan Maxima, which belonged to another missing man — Tom Meo — was found on the DiNardo’s farmland. He is currently being held on $5 million bail. DiNardo earlier made a lower bail amount and was freed Tuesday evening, the day after his initial arrest.

Weintraub said police would "continue digging and searching that property until we're satisfied that they are not there." "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," he added.

Meo, Finocchario, Mark Sturgis, 22, and Jimi Tar Patrick, 19, were all last seen a week ago. Patrick's family members said Sturgis and Meo worked together and Finocchiaro was a mutual friend. 

According to a friend of Meo, DiNardo sold guns and marijuana and in the past has bragged about having someone killed over a debt. "I can tell you on multiple different occasions, on multiple different accounts, from multiple different people, including myself – Cosmo has spoken about weird things like killing people and having people killed," Eric Beitz, 20, of Bensalem, told Philly.com, adding that he believes DiNardo is mentally unstable.

Read: Case Of 4 Missing Pennsylvania Men Has ‘Mind Boggling’ Scope, Authorities Say

According to the report, DiNardo and Patrick both attended Holy Ghost Preparatory School in Bensalem.  DiNardo has not been charged in the death of Finocchario so far, but Weintraub reportedly said he was pursuing homicide charges. 

Five local law enforcement agencies, Pennsylvania state police, the FBI and United States Marshals are all involved in the investigation.