DOYLESTOWN, Pa. — Prosecutors charged two men Friday with homicide and a host of other crimes in the killings of four who went missing in Pennsylvania last week, setting off an intensive search that gripped this wealthy region north of Philadelphia. 

On Friday, officials said that they had filed charges against a man who a day earlier confessed to his role in killing missing four and another series of charges against another man they said was involved in some of the deaths.

Authorities said that the missing men were all shot after meeting with Cosmo Dinardo, the 20-year-old man at the center of the investigation, centered on marijuana deals.

Matthew Weintraub, the Bucks County district attorney, said officials were focused on bringing home the remains of the men who went missing and prosecuting those responsible.

"We're here to seek justice for them," Weintraub said at a briefing Friday. "That is our commitment."

Dinardo had been the sole person of interest identified by authorities so far. In a court filing Friday, prosecutors charged him with two dozen total counts including four counts of criminal homicide, another four counts of conspiracy involving a criminal homicide and a range of counts relating to inflicting serious bodily injury and abusing a corpse.

The prosecutor's office also charged a second man, Sean M. Kratz, with three counts of homicide as well as similar charges levied against Dinardo, including inflicting serious bodily injury and abusing a corpse, according to another court filing.

According to prosecutors, Dinardo killed the first man who went missing — Jimi Patrick, 19 — and buried him in a grave on land owned by his parents. Dinardo and Kratz are both charged with three other slayings that followed two days later and accused of burying the three men in a group grave where human remains were found this week.

With the charges on Friday, authorities confirmed that the four missing men — all between the ages of 19 and 22 — who had been sought for days were all dead. Weintraub had said a day earlier that officials found the body of one of the missing men at a farm not far from the Delaware River along with other human remains in a 12-foot-deep "common grave" on the property.

Dinardo, whose parents own the farm that investigators were scouring, on Thursday confessed to "his participation" in the killings of the four men, his lawyer said. He was already in custody after being accused of stealing and trying to sell a car belonging to one of the missing men.

"He confessed to his participation or commission in the murders of four young men," Paul Lang, the lawyer, told reporters. "In exchange for that confession, Mr. Dinardo was promised by the district attorney that he will spare his life by not invoking the death penalty."

Lang did not respond to a message seeking comment Friday. It was unclear whether Kratz has an attorney. The Philadelphia Inquirer newspaper first reported Friday that Kratz was in custody in connection with the case after being arrested in Philadelphia.

Police in Philadelphia referred questions about Kratz to the Bucks County district attorney's office, which said no one was available to answer questions before a briefing scheduled for Friday afternoon.

Even after Dinardo's confession, questions had remained regarding including whether anyone else participated in the slayings. Weintraub's office said he had "no response" to Lang's statements regarding a confession, and a briefing set for Thursday night was canceled. Another news conference scheduled for Friday morning was postponed and then rescheduled for a government building in Doylestown early Friday afternoon.

Weintraub's office had declined to confirm or deny media reports that Dinardo implicated a co-conspirator and that someone was taken into custody late Thursday night. Weintraub planned to lay out the case in detail Friday afternoon, according to a spokesman.

On Friday, even with Dinardo in custody, the extent and conditions of his apparent plea deal remained unknown. He was briefly seen in public after the confession when he left the courthouse in Doylestown. When reporters asked Dinardo — wearing glasses, an orange jumpsuit and handcuffs — what he would say to the relatives of the victims, he responded: "I'm sorry."

Authorities have said that Dinardo has a history of "severe mental illness" and had been committed to a mental health facility after an episode in which he fired a shotgun. No one answered when a Washington Post reported visited the address listed for the 20-year-old in court filings.

The search focused on the extensive property - owned by Dinardo's parents, Antonio and Sandra, according to prosecutors - in Solebury Township. Not far from the farm, shops line Route 202, with signs advertising fresh eggs and organic food, and a few miles away sits historic New Hope, a popular tourist spot.

Inside the farm, investigators have been at work digging deep into the ground. Aerial footage shows teams searching under a large tent, and Weintraub has said they are enduring stifling heat as they painstakingly search the property. The FBI has sent an evidence response team to help with the investigation and is helping local detectives manage incoming tips.

On Friday morning, a heavy law enforcement presence remained at the entrance to the farm amid heavy rain.

Officials said Thursday they had identified the body of Dean Finocchiaro, 19, found in the common grave. Finocchiaro, along with 21-year-old Thomas Meo and 22-year-old Mark Sturgis, has been missing since July 7. Patrick, a 19-year-old who just finished his first year at Loyola University in Baltimore, vanished two days earlier and, according to authorities, was killed first.

Meo and Sturgis are good friends and work together, according to court records. Local media reports say that Dinardo and Patrick attended the same preparatory school in Bensalem, while Dinardo and Finocchiaro had both posted on a Facebook page for buying and selling all-terrain vehicles.

Another vehicle helped authorities put Dinardo behind bars while they investigated the case. Meo's girlfriend last heard from him in a text message on July 7, according to court records, and he did not show up for work on July 8. Neither did Sturgis.

The next day, Meo's mother reported him missing. Cars belonging to Meo and Sturgis were then found about two miles apart, and Bucks County detectives interviewed a man from Bensalem, who said that Dinardo had offered to sell him an older model Nissan Maxima for $500.

Investigators say this is Meo's car. When they found it, Meo's insulin kit - needed to treat his diabetes - was found inside. Officials say Meo could not survive without the kit.

Residents expressed surprise at the mystery unfolding around them, something highly unusual in this area. 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."

Neighbors on the cul-de-sac where Dinardo lives in Bensalem described him as a good kid who went out of his way to help others, such as volunteering to shovel them out during snowstorms and refusing payment.

"Beautiful family," said a neighbor, who spoke on the condition of anonymity. "I don't know what went wrong with the kid. Great kid. Just saw him last week. Never a sign of problems."