The man charged with killing his brother and his brother’s entire family in Colts Neck last year was about to be cut off from their once-thriving technology company after money went missing, according an affidavit unsealed Monday.

Paul Caneiro, 51, is accused of gunning down his brother, Keith, before killing his sister-in-law, 8-year-old niece and 11-year-old nephew. He then set fire to their house and later his own house, authorities say. His attorneys have maintained he is innocent and said he would never hurt his family.

The criminal complaint released Monday says otherwise.

Paul Caneiro was a minority owner in the Asbury Park-based technology consulting business Square One, but his brother, Keith, was frustrated with the amount of money Paul was spending from their business accounts, the affidavit said. It said Keith, who had a 90 percent stake in the company, told business associates he planned to cut payments made to Paul’s wife, who was collecting money on her husband’s behalf after he was injured in a car wreck and deemed disabled.

Keith Caneiro also wanted those payments to stop flowing until he found the source of money that had gone missing, he told the two business associates in an email, according to the complaint. Keith forwarded that email to another brother on Nov. 19, the night before he was found dead outside his Colts Neck mansion, according to the complaint.

A 16-count indictment, returned by a grand jury on Monday, also accuses Paul Caneiro of stealing $75,000 from his brother.

The affidavit of probable cause provides new insight into the grisly slayings. Monmouth County Prosecutor Christopher Gramiccioni previously told reporters the motive was “financial in nature” but declined to elaborate.

NJ Advance Media reported in December that Square One, which once raked in as much as $5.5 million in revenue, was a shell of its former self, largely staying afloat by a contract with one client, the Doris Duke Charitable Foundation. The two brothers also equally owned a pest control business that operated out of the same Asbury Park office.

The affidavit says Keith Caneiro told his other brother that he wanted to sell one of the businesses.

The affidavit also lays out in disturbing detail how the events of Nov. 20 unfolded and the evidence detectives have collected in their case against Paul Caneiro. He is charged with four counts of first-degree murder and remains behind bars at the Monmouth County jail in Freehold.

Caneiro’s attorneys, Robert A. Honecker Jr. and Mitchell J. Ansell, said Monday evening they are reviewing the indictment and the description of the evidence in the state’s case.

The state’s case

On Nov. 20, around 1:30 a.m., a surveillance video from one of numerous cameras attached to Paul Caneiro’s Ocean Township home films him walking to his surveillance recording system in his garage, the report states. The system stops recording at that time. He would go on to tell authorities who interviewed him that he doesn’t recall why he turned off the system, but that it was causing his Wi-Fi network to slow down. Detectives determined that the system is hard-wired and doesn’t rely on Wi-Fi, the report said.

Shortly before 2 a.m., a surveillance camera from a home behind Paul Caneiro’s Tilton Drive house captures headlights leaving his driveway.

At 15 Willow Brook Road in Colts Neck, Keith Caneiro’s sprawling million-dollar mansion, a neighbor calls 911 at 3:33 a.m. and reports hearing five gunshots in the area. Another neighbor on Willow Brook Road told detectives she recalls hearing the same number of gunshots at 3:10 a.m.

Authorities say Paul Caneiro shot his brother in the lower back before firing four shots into his head. His body was found on the front lawn. Jennifer Caneiro, 45, was found dead on the stairs leading from the basement to the first floor of the home, the report said. A medical examiner determined she died from a gunshot wound to her head and multiple stab wounds to her torso.

Both Sophia Caneiro, 8, and her 11-year-old brother, Jesse, were stabbed multiple times, the report stated. Sophia was found on the landing of the stairs between the first and second floors. Her brother was found in the kitchen.

The grisly discoveries were made around 12:40 p.m., when Colts Neck police responded to the home for a report of a fire. Authorities say Paul Caneiro set fire to the basement of the home after the killings, but it’s unclear how the fire churned for so long unnoticed.

An aerial view of authorities responding to a massive fire in Colts Neck on Nov. 20. (Andrew Mills | NJ Advance Media for NJ.com)

That morning, at 4:08 a.m., the surveillance camera behind Paul Caneiro’s Ocean Township house on Tilton Drive observes headlights of a vehicle returning to the home.

The Ocean Township police respond to the Tilton Drive house at 5:01 a.m. to a report of smoke inside the residence. The fire was reported by a woman who fled the house, according to the 911 call, obtained by NJ Advance Media. She reported that everyone evacuated the home safely and she didn’t know where the fire originated.

Responding police officers found a fire burning in the back of the house, the affidavit said. A small fire was also discovered on the lower part of the garage door.

Paul Caneiro’s wife and the couple’s two daughters were sitting in a car outside the house when police arrived, the report said.

A red gas can and a charred, rubber glove were found next to the white Porsche Macan Paul Caneiro was renting while his car was being serviced at the dealership, according to the report.

Inside the house, the report said, police found two lighters, including one that was on a small table inside the living room near the front door. Representatives with the Monmouth County Fire Marshal’s Office determined that the fire was incendiary and was started by combustible gases.

Paul’s wife told investigators that she didn’t know anyone who would want to cause harm to her family.

Gramiccioni, the prosecutor, previously told reporters Caneiro set fire to his own residence both as an attempt to destroy evidence he had brought back from Colts Neck and as “a ruse” to make it appear the extended Caneiro family had been targeted.

The next day, on Nov. 21, Caneiro was arrested and charged with aggravated arson after lighting his own house on fire with his family inside, authorities announced.

But that paled in comparison to the evidence authorities said they soon found.

Two days later, detectives went through Paul’s Tilton Drive home with a K-9 looking for blood, the report said.

It didn’t take them long to find a plastic container filled with blood-stained clothing and a bloody latex glove, the complaint said. Police also said they found a 9 mm bullet that matched a casing found at Keith Caneiro’s Colts Neck house.

Outside the house, a search of a Porsche Cayenne turned up a backpack with a laptop, Paul Caneiro’s passport, the barrel of a 9 mm Sig Sauer gun, a gun silencer and a night-vision tool, according to the report.

Police also found in Paul Caneiro’s basement a large gun safe with many guns and a variety of ammunition. Neighbors previously told NJ Advance Media that Paul Caneiro is a gun enthusiast and belonged to a local range.

On Nov. 27, detectives received results from the New Jersey State Police DNA Laboratory that showed the blood found on the clothing in Paul Caneiro’s basement matched Sophia’s, according to the report.

Her blood was also found on a knife left at the Colts Neck residence, the report said.

On Nov. 29, Paul Caneiro was charged with four counts of first-degree murder in the death of his brother, his sister-in-law and his niece and nephew. Authorities announced the charges at a standing-room-only news conference filled with reporters from news outlets around the country.

It’s likely Caneiro’s case won’t go to trial until 2020, Gramiccioni has said.

Alex Napoliello may be reached at anapoliello@njadvancemedia.com. Follow him on Twitter @alexnapoNJ. Find NJ.com on Facebook.

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