This post has been updated.

On the evening of Nov. 19, 2018, Keith Caneiro forwarded an email to one of his brothers.

In the email, the New Jersey-based CEO raised concerns about thousands of dollars that had disappeared from two businesses he shared with his other brother Paul Caneiro, according to a probable cause affidavit that was released Monday and published by the Asbury Park Press. Suspicious that Paul had something to do with the missing funds, Keith wrote that he had decided to stop paying his brother’s salary until the money was located.

Less than 24 hours later, a 911 call came in from one of Keith’s neighbors. The businessman’s mansion in Colts Neck, N.J., was on fire. But when police and firefighters arrived at the home, they discovered a much more grisly scene.

Keith, 50, was lying dead on the front lawn. He had been shot once in his lower back and four times in his head, the affidavit said. Inside the home, firefighters came across three more bodies: Keith’s wife, Jennifer, 45, and the couple’s two young children, 11-year-old Jesse and 8-year-old Sophia. According to the affidavit, Jennifer had been shot in the head and stabbed. Both children were stabbed multiple times.

The crime rocked the quiet community about 50 miles south of New York, with speculation running from a mob hit to a random act of violence. Now, prosecutors say that email was just one piece in a mountain of evidence that pointed them to the real culprit: Paul.

On Monday, a Monmouth County grand jury returned a 16-count indictment against Paul, alleging he stole about $75,000 from his brother between January 2017 and November 2018, the Asbury Park Press reported. Court documents, which were also unsealed on Monday, revealed that the brothers had been feuding about money for months before that November day.

In a joint statement emailed to The Washington Post on Tuesday, attorneys for Paul, 52, said they are reviewing the indictment and “discussing potential issues” related to it.

“Under the court rules, we now have access for the first time to all of the state’s evidence in this matter which they believe supports their theory of the case,” wrote attorneys Robert A. Honecker Jr. and Mitchell J. Ansell. “We also have to review that evidence to identify any issues that may relate to the case.”

Paul was first arrested shortly after the Caneiro family was found, but not for murder or for setting his brother’s house on fire. He was charged in November with aggravated arson for allegedly starting a fire at his own home in a neighboring township hours after his brother’s death. Paul’s wife and two daughters were home at the time of the fire but were unharmed, The Washington Post’s Deanna Paul reported.

More than a week later, prosecutors announced they were filing additional charges against Paul — this time, accusing him of killing the family of four and setting both house fires in an attempted coverup. The fire at Paul’s Ocean Township home was suspected to be a “ruse designed to make it appear as if the overall Caneiro family was somehow targeted,” Monmouth County prosecutor Christopher Gramiccioni said at a news conference last November. He added at the time that investigators believed the motive behind the murders was “financial in nature,” but declined to provide further details.

Now, the probable cause affidavit spells out exactly how and why prosecutors believe Paul brutally killed his brother’s family.

According to the documents, a third brother, only identified as “C.C.,” told investigators about the email Keith wrote, in which he appeared to be cutting Paul off by no longer paying his salary. An office manager confirmed to authorities that Keith instructed “her to stop payment . . . because of arguments with Paul over money,” the affidavit said.

Additionally, C.C. said, “Keith indicated that he wanted to sell one of the businesses and that Keith told him that he was frustrated with Paul and the amount of money Paul spent from their business accounts.” Paul was a minority owner in Keith’s Asbury Park, N.J., technology consulting firm, Square One, the affidavit said. The pair equally owned a second pest control business.

The affidavit also presented evidence collected by investigators from Paul’s home, including a bullet that matched the casings found at the Colts Neck home, as well as a latex glove and a pair of jeans stained with blood. DNA testing later confirmed the blood belonged to Paul’s dead niece, the affidavit said. Inside a Porsche Cayenne parked outside the house, authorities found a 9mm barrel of a Sig Sauer gun along with firearm accessories such as a silencer and a night-vision attachment, according to the affidavit.

In November, Paul’s attorneys said he maintained his innocence, adding that his family “means more to him than anything else in this world,” NJ.com reported.

“There is absolutely no reason in the world for Paul Caneiro to have committed the crimes he is alleged to have committed,” Honecker and Ansell wrote in a statement to the news site. “He would never hurt any member of his family.”

The events leading up to what Gramiccioni described as “one of the most heinous cases” he has seen in Monmouth County began in the early morning hours of Nov. 20.

Surveillance cameras around Paul’s house stopped recording at 1:30 a.m., according to a separate affidavit also published by the Asbury Park Press on Monday. The last footage recorded showed Paul “walking into the garage, turning on the light and then walking toward the DVR system,” the affidavit said.

According to investigators, surveillance footage from houses nearby showed headlights leaving Paul’s home at around 2 a.m. and not returning until roughly two hours later.

At around 3:30 a.m., a Colts Neck resident who lived about three-and-a-half miles from Keith’s house called to report hearing “what sounded like five gunshots,” but responding officers were unable to locate the source, the affidavit said. Detectives later found another neighbor who remembered hearing “four to five loud ‘cracks’ consistent with gunshots followed by one single gunshot” just minutes after 3 a.m.

Shortly after 5 a.m., the Ocean Township Police Department responded to a report of smoke from inside Paul’s house, where his wife and two daughters also lived, according to police documents. Fires were found near the rear of the home and the garage, which authorities later alleged were set by Paul himself.

Paul remains detained pending trial in the Monmouth County Correctional Institution, according to a Monday news release from the Monmouth County Prosecutor’s Office announcing the grand jury indictment. Paul now faces four counts of first-degree murder, two counts of first-degree felony murder and two counts of second-degree aggravated arson, among other charges. If found guilty, he could face a maximum sentence of life in prison.

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