Additional human remains were found inside the grave, but have not been identified yet.
Jimi Patrick, 19, of Newtown Township, has been missing since last Wednesday and Mark Sturgis, 22, of Pennsburg; Thomas Meo, 21, of Plumstead Township, and Dean Finocchiaro, 19, of Middletown Township, have been missing since Friday.
Meo is one of four men between 19 and 22 years old who went missing over several days last week within miles of each other.
Dinardo, of Bensalem, Pa., was being held on a $5 million cash bail after being arrested Wednesday; one day earlier, he had been deemed a "person of interest" in the missing-persons case after he was accused of trying to sell the vehicle belonging to one of the missing men.
Weintraub also confirmed that 20-year-old Cosmo DiNardo, whose parents own the farm, is a "person of interest" in the case.
Finocchiario was also last seen on Friday, while Patrick disappeared Wednesday, according to the paper. Levittown Now reported that Dinardo was suffering from mental illness, which hypothetically could have disqualified him from gun ownership. He is charged with stealing the 1996 Nissan Maxima and trying to sell it for $500 to a friend in Bensalem (where Dinardo lives).
Authorities near Philadelphia asked for the public's help and patience Monday as they search for four young men who disappeared over the past week in what they are calling a criminal investigation.
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Meo is diabetic, and his insulin kit and glucose meter were reportedly found in his auto. In exchange for DiNardo's cooperation, Lang said, prosecutors would not seek the death penalty. "We're making great progress, but there's so much more work to do", he said.
DiNardo has told investigators where the rest of the bodies are.
Authorities said all four victims had been positively identified.
Weintraub addressed the media not far from the location of one search, a multi-acre property along Route 202 near Aquetong Road in Solebury. "We are not sure what we are going to find there, but we are pretty confident that the investigation is proceeding in the direction that we believed that it would".
July 12: DiNardo is charged with receiving stolen property in connection with Meo's auto and his bail is set at $5 million.
Earlier Thursday, investigators worked to excavate a 12-foot grave found to hide human remains on the 90-acre farm.