D.C. police arrested Daron Dylon Wint near 10th Street and Rhode Island Avenue NE on the night of May 21. Wint was apprehended in connection with the killing of a Washington family and their housekeeper. (WUSA9)

Authorities said in court papers Friday that the brutal killings of the Savopoulos family in Northwest Washington probably involved a conspiracy of more than one person taking the victims captive and waiting more than 19 hours for a $40,000 ransom before killing them and setting fire to their multimillion-dollar home.

Savvas Savopoulos, 46, his wife, Amy, 47, and their housekeeper, Veralicia Figueroa, 57, were beaten and stabbed, according to the court papers — the arrest warrant affidavit written by police. The couple’s 10-year-old son, Philip, was found dead on a charred queen-size mattress in his bedroom. He had been beaten, stabbed and burned, police said in the document, and his room and others in the house were doused with gasoline.

The new details came as the first suspect identified in the slayings made his initial appearance in D.C. Superior Court. Daron Dylon Wint, 34, was arrested Thursday night after a two-day manhunt and charged with first-degree murder while armed.

Police said in the affidavit that the elaborate crime probably “required the presence and assistance of more than one person.” The document also says that police think “all four decedents were held captive by Mr. Wint and others.” Police did not elaborate, but they have said other suspects have not been ruled out.

Wint was captured in Northeast Washington after a task force of federal marshals and police tracked him to New York and back to the District over two days.

Wint so far is charged only in the death of the family patriarch, a wealthy socialite and business executive who ran American Iron Works, a large supplier of iron and steel to construction projects. Officials said additional charges are likely in the deaths of the wife, son and housekeeper.

Wint appeared in court with his wrists and ankles shackled, escorted by three marshals.

He said only his name at the hearing. At times, he shook his shoulder-length dreads out of his eyes.

His attorney, Natalie Lawson of the Public Defender Service, said in court that the case was “based on speculation and guesswork.” She added: “He is innocent. There is no link to the killings or the death of the decedent. There is nothing linking him to these deaths.”

Magistrate Judge Errol R. Arthur ordered Wint held until his next court appearance June 23, saying there was “a lot of circumstantial evidence here, but it all points to the defendant.”

The Savopoulos family on Friday thanked law enforcement for the arrest.

“While it does not abate our pain, we hope that it begins to restore a sense of calm and security to our neighborhood and to our city,” they said in a statement issued by a family spokeswoman.

The police affidavit filed in court Friday offers new details about how the family and Figueroa were held and killed in the three-story home on Woodland Drive NW, near the vice president’s mansion. Police have said that Wint once worked for Savopoulos’s American Iron Works firm in Hyattsville, Md., but have not offered a motive. D.C. Police Chief Cathy L. Lanier has assured residents that the family was targeted and the crime was not random.

Assistant U.S. Attorney Emily Miller said Wint’s DNA was found on discarded pizza left in the room where the three adults were found dead.

She said police found a fingerprint on a water bottle at the house, and that prosecutors were seeking to compare it with Wint’s fingerprints.

Police also have been examining confusing and mysterious text messages sent among the Savopouloses and another housekeeper, whom they repeatedly told to stay away from the home. They also investigated the actions of Savopoulos’s assistant, who delivered the $40,000 to the house May 14 in the moments before the killings.

In the affidavit, police said the assistant told detectives that Savopoulos called him on the morning of May 14 and told him to go to the iron company, pick up a package and deliver it to the D.C. house.

The assistant told police two versions of how he obtained the package — a red bag filled with $40,000 that had been withdrawn by other Iron Works employees from one of the company’s accounts at Bank of America.

The assistant said Savopoulos instructed him to take the money from the red bag and put it in a manila envelope, then place it inside a red car parked in the garage at the family home. The assistant then texted another person a photo of a red bag with what appeared to be two bundles of money wrapped in white bands. Authorities declined to comment on the assistant’s text or say who received it.

The arrest affidavit says matter-of-factly that “after the money was delivered, the four decedents were killed.”

Police said Wint took the family’s blue Porsche, which was found later that day burned in a church parking lot in Prince George’s County, two miles from Wint’s parents’ home.

Wint’s capture was precipitated by the pizza the family ordered during the ordeal. The affidavit says Amy Savopoulos ordered two pizzas from a Tenleytown Domino’s at 9:14 p.m. May 13 and instructed the driver to leave the boxes on the front porch, ring the bell and leave, saying she was nursing a sick child. The delivery person reported seeing the house completely dark, except for the porch light.

Police said they found two Domino’s boxes in the bedroom where the three adults were found.

A cheese pizza had not been eaten, but a pepperoni pie had been partially consumed. Police used a federal lab to expedite a DNA test and said a match came back for Wint, who has an arrest and conviction record in Maryland.

U.S. Marshals Cmdr. Robert Fernandez, who runs the Capital Area Regional Fugitive Task Force, said his agents were summoned Tuesday after D.C. police learned Wint’s name for the first time.

By Wednesday, they believed he had fled to Brooklyn, where he has family and friends. But a raid on an apartment there later that night turned up empty.

“He had just left,” Fernandez said. “We barely missed him.”

Fernandez said his team “worked through the night,” and Thursday they learned Wint might be back in the Washington area, at a Howard Johnson hotel in College Park, Md. By that time, D.C. police had released his name and announced a $25,000 reward.

But as agents were trying to learn what room he was in, Fernandez said a surveillance team noticed Wint leaving in one of two vehicles that pulled out of the parking lot shortly before 11 p.m.

Police followed a box truck and a white Chevrolet Cruze sedan heading toward the District. “It was obvious they were traveling together,” he said.

About 25 unmarked police cars and a helicopter from Prince George’s County — tracking the vehicles with a thermal-imaging camera — followed them into the District. Near Rhode Island Avenue and 10th Street NE, Fernandez said an unmarked police car got between the truck and the sedan, and other cars pinned them. Officers, some armed with semiautomatic weapons, detained five people from both vehicles.

Fernandez said Wint was in the back seat of the sedan, which had a female driver and passenger. He said two men were in the truck. They were seated on a curb and handcuffed. “They had no idea they were being followed,” he said.

Authorities said they found $10,000 in the truck; Fernandez said he saw money stuffed into the side door. Court documents say authorities found money orders exceeding $10,000 and a large stack of $100 bills, the same denomination delivered to Savopoulos in the $40,000 delivery.

D.C. police said only that Wint was arrested. A spokesman said none of the others were charged with crimes, but offered no explanation. Wint said everyone in the vehicles surrendered without incident.

“They were in the face of overwhelming odds and force,” he said.

Lynh Bui and Clarence Williams contributed to this report