The white man suspected in the burnings of three historically black churches in Louisiana will remain in jail, denied bond Monday by a judge, as state prosecutors added new charges declaring the arsons a hate crime. Holden Matthews, 21, the son of a sheriff's deputy, entered his not guilty plea via video conference from the St. Landry Parish jail. The judge set a September trial date.

In denying bail, state District Judge James Doherty sided with law enforcement officials who said they worried Matthews would try to flee the area or set more fires.

Holden Matthews WWLTV

"We felt that he was an immediate risk to public safety," said Louisiana Fire Marshal Butch Browning. "In my mind, I felt another fire was imminent."

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Testifying in court, Browning outlined a litany of evidence, including some new details of the investigation that he said tied Matthews to the torching of the three churches over 10 days.

"The evidence we have was unequivocal," Browning said. Later he added: "He has clearly demonstrated the characteristics of a pathological fire setter."

The fire marshal described cellphone records placing Matthews at the fire locations, and he said images on the phone showed all three churches burning before law enforcement arrived and showed Matthews "claiming responsibility" for the fires.

Matthews, who had no previous criminal record, was arrested Wednesday on three charges of arson of a religious building. Prosecutors filed documents Monday adding three more charges, accusing Matthews of violating Louisiana's hate crime law, confirming that they believe the fires were racially motivated, a link authorities had previously stopped short of making.

Browning said federal officials also are considering filing additional federal hate crime and arson charges against Matthews.

Matthews, shackled and wearing an orange prison jumpsuit, did not speak during the hearing. His parents watched their son's appearance on video conference from the courtroom; his father, Deputy Roy Matthews, repeatedly wrung his hands and at one point left the room in tears.

Roy Matthews had no knowledge of his son's alleged crimes, St. Landry Parish Sheriff Bobby Guidroz, who employs the father, previously said. Guidroz said the elder Matthews "broke down" when he called him into his office to inform him of the allegations, and later helped facilitate his son's arrest.

The fires, all started with gasoline, occurred in and around Opelousas, about 60 miles west of Louisiana's capital city of Baton Rouge.

Matthews' arrest came a little more than two weeks after the first blaze at the St. Mary Baptist Church on March 26 in Port Barre, a town just outside of Opelousas. Days later, the Greater Union Baptist Church and Mount Pleasant Baptist Church in Opelousas were burned. Each was more than 100 years old.

The churches were empty at the time, and no one was injured. But at one location, two occupants of a nearby home had to evacuate when the siding on the home started to catch fire from the church.

The fires set the community on edge. Gov. John Bel Edwards said the church burnings were a reminder "of a very dark past of intimidation and fear."

Matthews' attorney, Quincy Cawthorne, questioned some of the evidence cited by Browning and said Matthews didn't have the financial means to be a flight risk. He also objected to suggestions that the house near one of the churches was intentionally set on fire, putting the residents' lives in danger.

Prosecutors, through Browning's testimony, gave more insight into the evidence that law enforcement used to build their case against Matthews.

The fire marshal said a receipt shows Matthews bought a gas can and a package of oil rags similar to those found at the site of the fires. A lighter and the package of oil rags, missing some of its contents, were found in Matthews' truck, Browning said. He said Matthews documented the fire on his cellphone, while video surveillance in the area around the churches showed a truck similar to the one Matthews drives. Matthews had copies of news reports about the fires on his phone as well, Browning said.

"He actually superimposed himself on those news reports, claiming responsibility for these fires," Browning said.

In addition, Browning said video on Matthews' phone showed a conversation with a friend before the fires in which he talked about burning churches and using gasoline to do it.

Browning said previously authorities are eyeing Matthews' interest in "black metal," an extreme subgenre of heavy metal. The music has been linked, in some instances, to fires at Christian churches in Norway in the 1990s.

The fire marshal said Matthews posted on Facebook about and showed interest in a movie called "Lords of Chaos," a recent film about the Norwegian black metal scene and associated violence in the 1990s.