A Florida man faces multiple charges, including threatening a mass shooting and impersonating law enforcement, deputies said.

Damien Allen, 22, was arrested Tuesday night after the Palm Beach County Sheriff's Office said he was potentially planning an attack and had engaged in threatening communications through online platforms.

According to a probable cause affidavit, the sheriff's office was notified of an FBI Guardian Tip, similar to a Crime Stoppers tip, that Allen was possibly planning an attack.

Investigators said Allen used various online platforms, including TikTok, Instagram and Discord, to post threats about committing a mass shooting.

The affidavit said Allen previously talked to Natalie Rupnow, 15, who died after carrying out a mass shooting at a school in Madison, Wisconsin, on Dec. 17, 2024.

During their investigation of Allen, the arrest report said he posted a video on Instagram on Oct. 8, 2022, with him inside a Ford Crown Victoria, which is commonly used by law enforcement. Deputies said the video started with Allen inside the driver's seat of the vehicle and a computer that looked like a Palm Beach County sheriff's laptop.

"After Allen shows the laptop, he shows a rifle rack behind the seat with a rifle in the vehicle," the affidavit said.

The arrest report said that Rupnow and Allen communicated on TikTok in May 2024, where they talked about a variety of weapons, ammunition, bulletproof vests, smoke grenades and AR500 steel plates. The report said they communicated online through at least Sep. 26, 2024.

"My loadout is set up for war," Allen said on May 23, 2024, according to the affidavit. "I got 7 places I would, Strike the police dept. also Gorilla warfare tactics, Ambushing and blitz."

The report said that based on his communication with Rupnow, it was clear that Allen "unequivocally" made written threats to conduct a mass shooting at seven different locations.

"He is armed with at least two firearms, which he can use to shoot 9mm bullets from, and he has at least 118 9mm bullets (5 pistol magazines, which hold 17 9mm bullets and another magazine, which holds 33 9mm bullets).

The report also said that Allen and Rupnow communicated on June 7, 2024, with Allen stating, "We go down together."

Rupnow replied, "Correct," and "I love you."

The affidavit said at first they thought, based on his postings, that Allen was a Palm Beach County deputy because he was dressed "in a full class B PBSO uniform." However, they later determined that Allen was not a PBSO deputy.

The report also said that he posted videos of himself wearing a silver PBSO star badge and the same gun belt, gun, Taser and holsters that PBSO deputies wear.

The sheriff's office said they are still investigating to see how he obtained the law enforcement gear.

Allen, who did not have a previous arrest record, is being held at the Palm Beach County jail without bond.

This story was originally published by Scott Sutton with the Scripps News Group in West Palm Beach, Florida.