A fire damaged the mosque where Omar Mateen, the mass shooter who killed 49 people at Pulse nightclub in Orlando, worshipped. Investigators say they have video that shows a person approaching the mosque and a fire igniting. (Reuters; Photo: St. Lucie County Sheriff’s Office)

A man has been arrested in the arson fire early Monday at the Florida mosque where Pulse nightclub shooter Omar Mateen occasionally worshiped, authorities announced Wednesday.The suspect was not immediately named, and the St. Lucie County Sheriff’s office scheduled a news conference for Wednesday evening

The St. Lucie County Sheriff’s Office said emergency crews responded to the Islamic Center of Fort Pierce shortly after midnight and extinguished the flames that were spilling out of the mosque.

The State Fire Marshal’s Office; Bureau of Alcohol, Tobacco, Firearms and Explosives; and the FBI have investigated incident as arson, according to the Associated Press. Investigators are also trying to determine whether it was a hate crime.

“A fire at any place of worship is alarming, regardless of the circumstances,” the St. Lucie County Sheriff’s Office said in a statement. “Video captured at the Fort Pierce Islamic Center shows an individual approached the east side of the building just moments before a flash is seen and the fire starts.”

Surveillance footage released by St. Lucie County Sheriff's Office shows a flash and a man running from the scene around the time that a Florida mosque was intentionally set on fire, according to police. (St. Lucie County Sheriff’s Office)

Authorities said Monday afternoon that the suspect is believed to be a white or Hispanic male who pulled up to the site about 11:40 p.m. on a Harley Davidson-style motorcycle, wearing jeans and a military-style boonie hat.

Surveillance video that was released to the public shows what appears to be a motorcycle driving by the area minutes before midnight. It appeared that the man was carrying paper and a bottle filled with liquid, police said. Then, seconds after the flash, a man is seen running from the scene.

The fire came just hours after the 15th anniversary of 9/11 and at the beginning of Eid al-Adha — the holiday of the sacrifice. As The Washington Post’s Pamela Constable noted, the three-day Islamic festival “commemorates the willingness of Ibrahim, the figure known as Abraham in the Bible, to follow God’s command to sacrifice his son Ishmael, who was later saved by an angel and lived to be 137.” The holiday is not to be confused with Eid al-Fitr, a separate festival that marks the end of Ramadan.

An undated photo from a social media account of Omar Mateen. (Myspace via Reuters)

The Islamic Center of Fort Pierce had an Eid prayer scheduled for 9 a.m. Monday. Those who wanted to worship were instructed to go to another mosque in the area.

“It is with a very heavy heart that we have to announce that last night around midnight, there was an arson attack on our Mosque,” the Islamic Center said in a statement. “Please keep us in your Du’as and prayers.”

Still, supporters showed up Monday morning to offer their condolences.

Ariana Borras, who is Hispanic, told the Associated Press that even though she is not Muslim, she can sympathize with those who are judged by the color of their skin.

She said the mosque fire “makes me scared for my skin color. There have been a lot of racial issues going on and there’s so much hate in the world right now.”

The fire caused substantial damage to the interior and exterior of the mosque, authorities said.

A spokesman for the Council on American-Islamic Relations Florida chapter said the “whole center is a crime scene now.”

Maj. David Thompson with the St. Lucie County Sheriff’s Office told reporters Monday morning that it was a “horrible tragedy not only for the Islamic center but for our community.”

“I don’t want to speculate on a motive,” he said. “We all know the implications of the date and the time of year that this is — the 9/11 anniversary. Is that related? I wouldn’t want to speculate, but certainly that is in the back of our minds.”

Thompson said “evidence has revealed that this fire was set intentionally.”

The mosque became a locus of attention in June after Mateen opened fire at Pulse, a gay nightclub in Orlando, killing 49 people and leaving dozens of others wounded. Mateen was killed in a shootout with police inside the nightclub.

Mateen occasionally attended the Islamic Center of Fort Pierce with his father and young son, Imam Shafiq Rahman told The Post in June. His three sisters were active volunteers at the mosque, which has about 150 congregants.

“He was the most quiet guy — he never talked to anyone,” Rahman said days after the Orlando massacre. “He would come and pray and leave.”

As The Post’s Mary Jordan previously reported, Mateen was at the mosque just two days before the deadly shooting rampage. On that evening, a Friday, “he knelt for over an hour on the green carpet of the Fort Pierce mosque, praying with his young son.”

The first American to carry out a suicide bombing in Syria, Moner Mohammad Abusalha, also occasionally worshiped here before he left his car outside the mosque in 2014, flew to Syria, burned his U.S. passport and blew himself up in an operation for an al-Qaeda affiliate.

The FBI looked for a potential connection between Mateen and Abusalha in 2014 and did not find “ties of any consequence,” aside from the two men knowing each other “casually” from attending the same mosque, said the bureau’s director, James B. Comey, on Monday.

But in the wake of Sunday’s attack in Orlando, there is a new focus on this small working-class town in South Florida and the mosque attended by two of the most infamous Muslim extremists with U.S. roots.

A board member at the Islamic Center of Fort Pierce in Florida talks about Orlando shooter Omar Mateen's attendance and demeanor. (Lee Powell/The Washington Post)

Ibrahim Hooper, national spokesman for the Council on American-Islamic Relations, said attacks against the American Muslim community are becoming a daily occurrence since Islamophobia moved into the mainstream.

“Unfortunately, within the past year, we’ve seen an unprecedented rise in bigotry in our society,” he said Monday, adding: “It’s becoming a great concern to the American Muslim community.”

Michael Parsons, whose parents live across the street from the mosque, told the Associated Press that since the shooting, “a lot of people have been driving by hollering and yelling expletives at the church or mosque or whatever they call it.”

“America was founded so people can believe what they want to believe and do what they want to do,” he said. “These guys flying the American flag on their trucks don’t really know what the freedom is they’re fighting for.”

In July, a witness said an intoxicated man made anti-Islamic remarks outside the mosque before assaulting a man who was there to worship, according to the Palm Beach Post.

“He said, ‘You Muslims need to go back to where you came from,’ ” the witness, Abdul Rauf Khan, told the newspaper. “He had been drinking. He was smelling bad. It was a vicious attack. He just started throwing punches.”

Authorities said at the time they were unable to confirm “any racially motivated comments” were made but the suspect, Taylor Anthony Mazzanti, was arrested and charged with felony battery, according to the newspaper.

Hooper said it is up to the majority that does not hold anti-Islamic views to stand up and say so.

He said Muslims feel “under siege like never before in our history” and need support from others to push back against “all the voices of hate.”

This story has been updated.

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