Federal authorities have charged a suspect with sending pipe bombs to 13 prominent Democrats and critics of President Donald Trump: Cesar Altieri Sayoc Jr., a 56-year-old Florida man.

Sayoc’s fingerprint was found on an envelope containing one of the bombs, and the investigation also found “a possible DNA connection,” FBI Director Christopher Wray said at a press conference Friday afternoon. Wray and other federal officials gave no indication that there might be other suspects or accomplices in the case.

Sayoc was arrested in Florida on Friday morning, after a week of suspicious packages containing homemade explosive devices put the nation edge. He’s been charged with five federal crimes, and faces up to 48 years in prison, if convicted.

No one was injured by the devices that Sayoc mailed to current and former officials, including President Barack Obama and former Secretary of State Hillary Clinton. But FBI Director Christopher Wray was adamant that the threat was real.

“Though we’re still analyzing the devices in our laboratory, these are not hoax devices,” Wray said, describing the bombs as consisting of PVC pipe, a small clock, a battery, wiring and potential explosive material.

Federal officials would not comment directly on the suspect’s motive, and whether he was inspired by political animus toward his targets. But Attorney General Jeff Sessions noted that he “appears to be a partisan.” Social media accounts that apparently belong to Sayoc contained graphic images and threats directed at some of the bombing targets, including former attorney general Eric Holder and former Vice President Joe Biden.

Sayoc has been apprehended, but in many ways the investigation into his attempted attack is just beginning to unfold. Here’s what we know so far.

Who is Cesar Altieri Sayoc Jr.?

Sayoc is from Aventura, Florida, just north of Miami.

He has an extensive criminal history, including an arrest for a past bomb threat in 2002, according to the Washington Post and the New York Times.

Sayoc apparently had tweeted threats to at least two bomb recipients, as well as pro-Trump memes and conspiracy theories. He’d also tweeted attacks at Republicans who opposed Trump.

Sayoc’s voter registration in Florida lists him as a Republican, according to state records. He registered in March 2016.

Where the investigation stands

FBI Director Christopher Wray said at a press conference Thursday that investigators were able to narrow in on Sayoc thanks to “a latent fingerprint from one of the envelopes containing an IED [improvised explosive device]” that had been sent to Rep. Maxine Waters (D-CA).

Federal authorities also seized a white van with decals on the windows, according to CNN and the South Florida Sun-Sentinel. Some of the decals, which included pro-Trump and anti-Democrat memes, matched tweets sent from social media accounts apparently belonging to Sayoc.

Officials would not comment on Sayoc’s motives, although Sessions noted that he “appears to be a partisan, but that will be determined by the facts as the case goes forward.”

He has been charged with five federal crimes: interstate transportation of an explosive, illegal mailing of explosives, threats against former presidents and certain other persons, threatening interstate communications, and assaulting current and former federal officers.

Officials warned that it might still be possible for other suspicious packages to turn up. Wray confirmed that 13 packages containing bombs have been recovered, including at least three discovered Friday: one addressed to New Jersey Democratic Sen. Cory Booker; one addressed to CNN’s offices in New York, but intended for former director of national intelligence James Clapper; and another sent to California Democratic Sen. Kamala Harris.

Federal prosecutors in the Manhattan will handle the case, and Sayoc could face up to 48 years in prison

President Donald Trump addressed the arrest and the ongoing investigation at an event in Washington, DC, on Friday, saying, “We have carried out a far-reaching federal state and local investigation trying to find the person or persons responsible for these events. … The events are despicable and have no place in our country. No place.”

What we don’t know