A Florida man who once had common neo-Nazi beliefs with his two roommates killed them after he converted to Islam, claiming they had disrespected his faith, police say.

Devon Arthurs, 18, of Tampa, told police he shot Jeremy Himmelman, 22, and Andrew Oneschuk, 18, on Friday at the Hamptons at Tampa Palms complex after becoming upset about widespread anti-Muslim sentiment, saying he “wanted to bring attention to the cause,” according to a police report obtained by the Tampa Bay Times.

Arthurs then briefly held an employee and customers hostage at the nearby Green Planet Smoke Shop, where he boasted that he had just killed his roommates, “blasting their head” with a semi-automatic pistol.

“Do me a favor and get the f— on the ground!” Arthurs yelled as he stormed into the store. “Why shouldn’t I kill you?”

He said he was upset that America was bombing Muslim countries, Tampa Bay police Detective Kenneth Nightlinger wrote in a police report.

Arthurs eventually freed his hostages and surrendered, making references to “Allah Mohammed” as cops took him to a patrol cruiser.

“I had to do it,” Arthurs said, according to the report. “This wouldn’t have had to happen if your country didn’t bomb my country.”

When asked if anyone else was hurt, Arthurs replied: “The people in the apartment, but they’re not hurt, they’re dead.”

Inside the Amberly Drive apartment, Himmelman and Oneschuk were found shot in the head and upper body, according to the police report.

Standing just outside the unit was another of Arthurs’ roommates, Brandon Russell, who was wearing US Army camouflage after returning to the apartment from the National Guard. Investigators searched the apartment’s garage and found an explosive known as HMTD — hexmethylene tiperoxide diamine, according to a criminal complaint filed in US District Court.

More than a pound of ammonium nitrate was also found in a package addressed to Russell, an admitted neo-Nazi whose bedroom was adorned with a framed photograph of Oklahoma City bomber Timothy McVeigh, who was convicted and executed for bombing the Alfred P. Murrah Federal Building in Oklahoma City in 1995. Russell admitted to being a member of a white supremacy group called the Atomwaffen.

Investigators also found empty bullet casings with fuses that could be used to detonate the explosive material. Russell was stopped by deputies on Sunday while driving south on US 1, but authorities did not indicate why he was pulled over, the Miami Herald reports.

Arthurs told investigators that all four men shared neo-Nazi beliefs prior to his conversion to Islam.

“Arthurs stated that for some time before the murders, he had been privy to Russell participating in online neo-Nazi internet chat rooms where he threatened to kill people and bomb infrastructure,” according to the complaint.

Arthurs, who remains jailed without bail, is facing two counts of first-degree murder, two counts of aggravated assault and three counts of armed kidnapping.

Himmelman and Oneschuk had recently moved to Florida from Massachusetts for a change of pace before being invited to live with Arthurs, Himmelman’s sister said Sunday.

Lyssa Himmelman told the Tampa Bay Times her brother and Oneschuk had been friends for about a year, with both men aspiring to enlist in the military. She said she didn’t know Arthurs that well, aside from his having extreme views that caused issues in the apartment.

They knew something was off with Arthurs about a week after moving in with him, Lyssa Himmelman told the newspaper. Both men were slated to move out Monday, just three days after they were found dead.

Messages seeking comment by The Post were not immediately returned Monday.