Remains of 1 of 4 missing Pennsylvania men found, says district attorney

— -- Human remains of one of the four missing Pennsylvania men have been found and identified, Bucks County District Attorney Matthew Weintraub said at a press conference early Thursday morning, shortly after midnight.

The remains, found on a sprawling farm in suburban Philadelphia, were those of Dean Finocchiaro, 19, of Middletown, Pennsylvania, Weintraub said.

"We have found human remains in an approximately 12-and-a-half-foot deep common grave that we have painstakingly dug with a lot of care so as not to damage any potential evidence," Weintraub said. "And I am very, very sad to say we can now identify Dean Finocchiaro, 19 years old, of Middletown, as one of the people that was found buried in that grave. He's been missing since Friday. We have notified his family that we have recovered his body."

Jimi Tar Patrick, 19, of Newtown Township, has been missing since Wednesday, while Finocchiaro, Mark Sturgis, 22, of Pennsburg, and Tom Meo, 21, of Plumstead, all disappeared Friday.

Weintraub did not mention the three other missing men, but added, "there are additional human remains inside that grave. So this painstaking process will go on. We're not done yet. This is a homicide, make no mistake about it. We just don't know how many homicides, we have yet to know the answer to that question."

Weintraub said, "I can't comment on the type of homicide that it is at this point, but I am comfortable classifying it as a homicide."

He reiterated that the investigation is two-pronged: "We’re still investigating the evidence, the investigation as you all know has taken two tracks –- recovery on one side and ascertaining what actually occurred on the other side, and we’re still avidly pursuing both of those avenues at this time."

Cadaver dogs led investigators to the grave, he said. "We had cadaver dogs, and I don’t understand the science behind it, but those dogs could smell these poor boys twelve-and-a-half feet below the ground.

And when asked what the condition of the remains are, he said, "I don’t want to comment on that but you can draw some logical conclusions -- they were found inside a twelve-and-a-half foot deep hole that we had to excavate."

Weintraub concluded the press conference, saying, "And I want to let you know that we reiterated over and over again, and it goes to say one more time to the families, that we're strong, and we're going to remain strong, and we're going to see this investigation to the end, and we are going to bring each and every one of these lost boys home to their families, one way or another and we will not rest until we do that."

On Wednesday, authorities arrested the son of the owners of the farm, 20-year-old Cosmo DiNardo, on charges he tried to sell Meo's 1996 Nissan Maxima a day after he was last seen. DiNardo's bail was set at $5 million in cash, the highest that Bucks County Magisterial District Judge Maggie Snow has ever set, she said.

At the press conference, Weintraub addressed DiNardo, saying, "I feel that we bought ourselves a little bit of time in charging Mr. DiNardo with the stolen car case today and getting that 5 million dollar bail. It is my hope that he does not post that but that is his prerogative of course if he can post it, but we’re going to start looking seriously at the homicide charges and in fact we already have pursued that option."

The DiNardo family's lawyer, Fortunato Perri Jr., had previously said in a statement that Cosmo DiNardo's parents are cooperating with law enforcement. "As parents, Mr. and Mrs. DiNardo sympathize with the parents and families of the missing young men and they are cooperating in every way possible with the investigation being conducted by law enforcement."

Weintraub said earlier that the relationship between the four men is not clear. But Sturgis' father "has said that his son and Meo are longtime friends who work in construction for him" and that "Finocchiaro is a mutual friend of theirs," according to The Associated Press.

Meo’s family also told authorities that he is good friends with Sturgis, according to a police criminal complaint filed Wednesday. Sturgis told his family he was going to meet with Meo on the day he went missing, the document states.

Sturgis did not show up for work on July 8, and he was then reported missing by his parents, according to the complaint.

ABC News' Karma Allen, Julia Jacobo, Morgan Winsor, Shauna Beni, Aaron Katersky, Eva Pilgrim and Emily Shapiro contributed to this report.