(CNN) On July 5, a young Pennsylvania man disappeared. Three other men went missing two days later.

On July 14, two cousins were charged with homicide and several other crimes after the missing men's bodies were discovered mutilated and buried on farmland in Bucks County.

In the space of those 10 days, the county would gain notoriety as the scene of grisly killings that stunned residents and investigators alike.

Based on four separate criminal complaints, several court hearings, public statements and other CNN reporting, here's what we know about how the killings transpired.

Day 1

Jimi Patrick, a 19-year-old college student who lives with his grandparents, leaves his home in Newtown Township at 6 p.m.

He agrees to meet with Cosmo Dinardo, 20, of nearby Solebury Township to buy 4 pounds of marijuana for $8,000, according to a criminal complaint.

Dinardo has a history of mental illness. He struggled with schizophrenia, said Bucks County District Attorney Matthew Weintraub. The year before, he was involuntarily committed to a mental institution, according to Bensalem Police Department Director of Public Safety Fred Harran.

Dinardo was also known to local authorities, and had over 30 contacts with Bensalem Police since 2011, said Harran. He was arrested in February and charged with possession of a firearm, which was illegal because of his mental illness, a criminal complaint states. The charge was dismissed in May because of an issue with the mental health paperwork and mental health delegate testimony, Harran said.

On this evening, Dinardo picks up Patrick at his grandparents' home and they drive to Dinardo's parents' sprawling farmland in Solebury, according to a criminal complaint.

He takes Patrick to a remote part of the property, where Patrick says he only has $800. Dinardo offers to sell Patrick a shotgun for that money, gives him the weapon, and then shoots and kills him with a .22-caliber rifle, Dinardo tells detectives after his arrest.

Dinardo drives the property's backhoe to that remote location and digs a hole about six feet deep, puts Patrick's body in the ground and buries him, the complaint states.

Day 2

Richard Patrick reports his grandson missing to Newtown police, telling them that he last saw the college student leaving their home the evening before.

Day 3

Sean Kratz allegedly joined his cousin Cosmo Dinardo in a plan to rob local men.

Patrick fails to show up for work at a restaurant-bar in nearby Doylestown. Acting on the missing-persons report, police ask the public for help locating Patrick.Patrick fails to show up for work at a restaurant-bar in nearby Doylestown.

Meanwhile, Dinardo sets up two other drug deals, according to a criminal complaint.

He first agrees to meet with Dean Finocchiaro, a 19-year-old from Middletown Township, and sell him a quarter-pound of marijuana for about $700.

Before the meeting, Dinardo picks up his cousin Sean Kratz, according to a complaint.

Kratz, 20, has a long criminal history, with all his arrests and charges related to theft or burglary.

Together, they decide that rather than sell marijuana to Finocchiaro, they will rob him, and Dinardo gives his mother's Smith-and-Wesson .357 handgun to Kratz, Dinardo later tells police.

The cousins drive to Finocchiaro's home, pick him up and bring him back to the Dinardo's family property. Finocchiaro is last seen at about 6:30 p.m. getting into an unidentified vehicle, according to police.

At the property, Finocchiaro is shot and killed in a barn, a complaint states. Kratz later tells police Dinardo shot Finocchiaro. Dinardo doesn't deny shooting Finocchiaro, but says his cousin shot the man first.

Dinardo wraps Finocchiaro's body in a blue tarp and then uses the backhoe to place him into a metal tank that Dinardo calls the "pig roaster," according to police.

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Later the same day, Dinardo makes plans to sell marijuana to Thomas Meo, a 21-year-old from Plumstead Township, according to a criminal complaint. Meo is with his friend and co-worker Mark Sturgis, 22, of Pennsburg.

Dinardo meets with Meo and Sturgis, and they follow him in Meo's 1996 Nissan Maxima to Dinardo's family home. A mobile license plate reader spots Dinardo's vehicle, a Silver 2016 Ford pickup truck, in Solebury at 7:49 p.m. The plate reader also spots Meo's Nissan Maxima seconds later, according to the complaint.

After arriving at the house, Meo and Sturgis get into Dinardo's truck and drive to the family's farmland property, where Kratz remained. As Meo and Sturgis exit the truck, Dinardo shoots Meo in the back, Dinardo later tells police. Meo collapses to the ground, screaming.

Sturgis starts to run away and Dinardo shoots at him, striking and killing him. Dinardo, out of ammunition, gets in the backhoe and drives over Meo, crushing him to death, the complaint states.

Dinardo uses the backhoe to pick up Meo and Sturgis and put their bodies in the same metal tank where he earlier had placed Finocchiaro's body. He pours gasoline into the metal tank and lights it, a complaint states.

Dinardo and Kratz then leave the farm without burying the burned bodies of the three men.

Later that evening, after Finocchiaro fails to show up for work, his mother Bonie Finocchiaro reports him missing to the Middletown Township Police Department.

Day 4

Meo and Sturgis fail to show up for work at their construction job. Worried, Melissa Fretanduno-Meo contacts the Plumstead Township Police Department to report her son missing.

In the afternoon, Dinardo and Kratz return to the farm and use the backhoe to dig a 12.5-foot-deep hole -- about 1/2-mile away from Patrick's grave -- and bury the "pig roaster" containing the charred bodies of Finocchiaro, Meo and Sturgis, the complaint states.

Dinardo then gives Kratz two firearms: a revolver and an Intratec Tec 9, the complaint adds.

At about 5 p.m., Dinardo contacts an unidentified male friend in Bensalem. They meet up and Dinardo offers to sell him a 1996 Nissan Maxima for $500 -- Meo's vehicle, according to a complaint.

Day 5

A man sits at the end of driveway in Solebury, as the search continues for four missing young men feared to be the victims of foul play.

After Sturgis fails to return home and show up for work, his parents report him missing to Pennsylvania State Police.

Police locate Sturgis' vehicle in an area known as Peddler's Village in Bucks County at 2:10 a.m., less than two miles from where the men were killed, a complaint states.

Two hours later, investigators locate Meo's 1996 Nissam Maxima at Dinardo's family home in Solebury. The keys and title to the vehicle, still in Meo's name, hang on the wall inside the garage, a complaint states.

Meo's life-saving diabetic kit sits unused in the car, according to the complaint. Meo's family tell police that he is insulin dependent and would not intentionally leave the kit behind.

Bucks County detectives interview Dinardo at 2:30 p.m., questioning him about his interactions with Finocchiaro on the night he went missing. Dinardo tells police that he picked up Finocchiaro at his home at about 7:00 p.m. on July 7 and that Finocchiaro asked him to drive to Langhorne for "a big coke deal," the complaint states.

Dinardo tells police that he told Finocchiaro he did not want to do that drug deal. He says he made Finocchiaro get out of his truck and then went fishing. Dinardo denies to police that he was in the Solebury area that evening.

Later that afternoon, Bucks County detectives interview Dinardo's friend from Bensalem. He tells them that Dinardo offered to sell him an older-model Nissan Maxima, according to the criminal complaint.

Day 6

From left: Jimi Patrick, Thomas Meo, Dean Finocchiaro and Mark Sturgis.

With four missing men on their radar, authorities kick their investigation into high gear.

The search team includes five local police departments, Bucks County detectives, Pennsylvania State Police and the FBI, according to Bucks County District Attorney Weintraub . Cadaver dogs and construction equipment are also enlisted to help.

Investigators search several locations for evidence. But a signal from one of the missing men's cell phones leads them to the Dinardo family's farmland property, according to CNN affiliate WPVI . They execute a search warrant there, a complaint states, hoping to find the men alive.

The same day, police arrest Dinardo for the unrelated and formerly dismissed firearms charge dating back to February. His bail is set at $1 million.

Day 7

Investigators gather under tents as they search a property in Solebury for four missing men.

Antonio Dinardo pays 10 percent of his son's $1 million bail in cash, setting Dinardo free.

About 50 local, state and federal law enforcement officers search the family's farmland for the missing men, according to Weintraub, who describes the effort as "all hands on deck."

Overhead video of the scene shows construction equipment and several makeshift tents shielding a team of investigators digging for evidence.

"I am still encouraged by the pace of the investigation, but as you can imagine, it's just massive in scope," Weintraub said.

"Take the biggest (investigation) you've ever seen and multiply it by a million," he later added.

Although Weintraub names Dinardo as a "person of interest" in the disappearances, he cautions that Dinardo is not accused of any crimes related to the investigation.

Day 8

Investigators with dogs search Solebury for four missing men.

With pressure mounting to find the missing men, Weintraub announces that officers have recovered several important pieces of evidence but that the investigation remains "wide open."

Police later re-arrest Dinardo for allegedly stealing and then trying to sell Meo's vehicle one day after he went missing, according to a criminal complaint.

In court, Weintraub says Dinardo has a history of schizophrenia. The judge says Dinardo is a "grave risk" and sets bail at $5 million.

Not long after, investigators discover the body of Finocchiaro, as well as other unidentified human remains, in a grave on the farmland property. The other remains are later identified as Meo and Sturgis.

At a midnight press conference, Weintraub announces the discovery of the bodies in a "common grave," and praises the cadaver dogs that led officers to the site. "This is a homicide, make no mistake about it," Weintraub says. "We just don't know how many homicides."

Day 9

District Attorney Matthew Weintraub updates the media on the search for four missing men.

Detectives interview Dinardo a second time, during which he admits lying to officers in his first interview. He confesses to his and Kratz's involvement in the murders, offering the gruesome details, according to a complaint.

Dinardo tells detectives where to find Patrick's body, buried in a separate grave on the property, says a criminal complaint. In exchange for that confession, Weintraub agrees not to pursue the death penalty against Dinardo, an attorney for Dinardo says.

As Dinardo is being led to a police vehicle, he tells a reporter "I'm sorry."

BREAKING: DiNardo just walked out. Told me he's sorry. Admitted to killing 4 men. @CBSPhilly pic.twitter.com/v9ay3lV7rp — David Spunt (@DavidSpuntCBS3) July 13, 2017

After Dinardo's confession , detectives detain and interview Kratz, who says he did not shoot anyone, but was present when Dinardo allegedly killed Finocchiaro, Meo and Sturgis, according to a complaint. He also directs police to a home in Upper Dublin Township, where detectives find the Smith-and-Wesson .357 handgun used in the killings and an Intratec TEC-9, the complaint states.

Day 10

A law enforcement official escorts Cosmo DiNardo to a vehicle in Doylestown.

The District Attorney's office files charges against Dinardo and Kratz , accusing them of multiple counts of homicide, robbery and abuse of a corpse, among other charges.

Dinardo faces four criminal homicide charges, and Kratz faces three criminal homicide charges, according to a criminal complaint.

In court, the judge enters a not guilty plea on the defendants' behalf and orders them held without bail.

Weintraub praises the work of the massive team of investigators who solved the case, and says that "we'd still be looking" for Patrick's body if not for Dinardo's confession.

"I don't know what convinced him (to confess)," Weintraub says. "I'd like to think that he wanted to help us get these boys home."