Federal authorities have confirmed that Florida resident Cesar Sayoc was arrested on Friday for allegedly sending more than a dozen mail bombs to high-ranking Democratic officials, celebrities, and media organizations in the last week.

Sayoc, 56, has been charged with five federal crimes, including interstate transportation of an explosive, illegal mailing of an explosive, and threats against a former president, according to Attorney General Jeff Sessions. He now faces up to 58 years in prison.

During a news conference on Friday, Sessions said that Sayoc "appears to be a partisan." The attorney general would not speculate on a motive, other than to say that it's "what you might normally expect." According to his social media profiles, Sayoc is a fervent Trump supporter, who often threatens violence against those the president vilifies. A white van that Sayoc reportedly lived out of was also covered in pro-Trump decals, and featured stickers of Trump critics with gun sights superimposed on their faces.

According FBI Director Christopher Wray, Sayoc sent a total of 13 improvised explosive devices to various individuals, including former President Barack Obama, former Vice President Joe Biden, and former Secretary of State Hillary Clinton. Sayoc left a latent fingerprint on one of the devices sent to Congresswoman Maxine Waters, Wray said, which the FBI traced back to Sayoc.

The FBI director added that each device consisted of roughly six inches of PVC pipe, a small clock, a battery, wiring, and potential explosive material. Contradicting widespread theories circulating on right-wing media, Wray emphasized that "these are not hoax devices."

Authorities said that an investigation is ongoing, and cautioned that it's possible more explosive devices are still in the postal system. Since Sayoc's arrest was first reported, two additional suspicious packages have been recovered—at the offices of Senator Kamala Harris and the home of billionaire donor Tom Steyer.

The United States District Court for the Southern District of New York is prosecuting Sayoc, and you can read the criminal complaint in full below.

Sayoc Complaint by John Del Signore on Scribd