At least some of the missing men are friends, but it's unclear how well they knew DiNardo, if at all.
The first to vanish was 19-year-old Jimi Patrick of Newtown Township.
Police say that, out of the remains found in a 12-foot grave on DiNardo's farm, they've only been able to identify Finocchiaro.
DiNardo, 20, then burned the bodies - three of them inside a drum - at his family's farm in Solebury Township, about 30 miles (48 kilometers) north of Philadelphia, the person said, adding that a co-conspirator was involved in the deaths of three of the men.
The farm Finocciaro's body was found on belong's to Dinardo's father. Lang says prosecutors agreed to take the death penalty off the table in return for DiNardo's cooperation.
"We have recovered several important pieces of evidence at this site, and at other locations", Weintraub said Wednesday as the search resumed for a fourth day. "And I'm not sure we'll ever know".
The men are believed to have been killed by Cosmo DiNardo, a schizophrenic from Pennsylvania, in relation to drug deals.
"Every death was related to a purported drug transaction, and at the end of each one there's a killing", the person said.
Fire and rescue crews on Thursday were using plywood to help shore up the deep grave as investigators worked inside under intense heat and choking dust.
According to the probable cause affidavit, Dinardo told investigators that he had agreed to sell Patrick (third photo) four pounds of marijuana for $8,000. DiNardo picked up Meo and Sturgis, then drove them back to the Solebury farm where Kratz was waiting.
Kratz provided investigators with a similar statement Thursday night, the affidavit says, but told police he did not shoot Finocchiaro. A second victim's vehicle was also found less than 3 miles away. DiNardo then continued to shoot at his body after he had died, The Daily Mail said.
The story took an unexpected turn on Wednesday, when Cosmo Dinardo was placed under arrest when he tried to resell it to a friend on the Nissan Maxima 1996 Thomas Moe.
The body identified was that of 19-year-old Dean Finocchiaro. The charging documents state that DiNardo told police, "When they turned their backs on me, I shot Tom in the back". Dinardo allegedly used the backhoe to lift their bodies up and put them in the metal tank with Finocchiaro's body, according to the complaint.
Beitz went on to say that DiNardo was known for dealing marijuana and selling firearms, aggressively searching for new customers - his mobile number was circulated regularly by resident teenagers.
Dinardo's parents own a construction and cement company called Cosan LLC. James Jackman, a 19-year-old who works at Antiques at the Old Church, right next to the farm, said that for this part of Pennsylvania to have a homicide investigation is "definitely out of character".
On Monday, the suspected killer was also charged with being in possession of a shotgun in an unrelated case from February.
A judge dismissed the charge in May, but the Bucks County district attorney's office authorized police to reinstate and refile charges last month. The suspect remains in custody on $5 million cash bail.
According to The Philadelphia Inquirer, the investigation shifted to an address in Northeast Philadelphia, where Kratz lived.
The defendants were jailed without bail and ordered held separately at a Friday afternoon hearing.