Joseph Schreiber, 32, of Port St. Lucie, is accused of setting fire to the Islamic Center of Fort Pierce last month.
The Trump supporter arrested last month for allegedly torching a Florida mosque attended by the Orlando nightclub shooter is being charged with a hate crime.
Joseph Schreiber, 32, was arrested September 14 after cops say surveillance footage shows him approach the Islamic Center of Fort Pierce then run away just prior to a flash of light.
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The mosque was once attended by Omar Mateen, who killed 49 people in the June massacre, as well as Moner Mohammad Abu Salha, an American who killed several Syrian government soldiers in a 2014 suicide bombing in Jabal al-Arbaeen after joining the Taliban.
Much of the mosque was gutted by the September 11 fire. Authorities noted the conspicuous timing of the blaze.
"We all know the implications of the date and the time of year this is, the 9/11 anniversary. Is that related? Certainly that is in the back of our minds," Major David Thompson of the Port St. Lucie Sheriff's Office said.
Congregants have since held prayer services in a part of the mosque that wasn't destroyed by fire as the imam says the public has donated about $80,000 to help rebuild the facility, the Orlando Sentinel reported.
Prosecutors announced the enhanced charge this week. Now, if convicted, Schreiber's potential sentence doubles to 30 years.
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In a statement released last month, the St. Lucie County Sheriff's Office said, "Schreiber is known to law enforcement and as such qualifies as a prison release re-offender that would impose a 30-year minimum mandatory sentence. He also qualifies as a habitual felony offender and could ultimately be sentenced to life in prison."
A Facebook page that appears to belong to the 32-year-old features multiple conservative fringe news posts that are critical of Islam and supportive of Donald Trump's candidacy for president.
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