Man who sent pipe bombs to several Trump critics, Democrats arrested by FBI

US authorities have charged a Florida man with five federal crimes in connection with the series of explosives-laden suspicious packages sent to several present and former high-ranking officials.

Cesar Sayoc, 56, was arrested Friday on charges of sending package bombs, which officials described as IEDs, to at least 10 present and former high-level government officials including former president Barack Obama, former vice president Joe Biden and former secretary of state Hillary Clinton.

"He (Sayoc) has been charged today 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," US Attorney General Jeff Sessions told reporters in a nationally televised news conference.

For these charges, Sayoc, who has a criminal history, faces up to 58 years in prison.

FBI Director Christopher Wray said that the suspect was identified on the basis of finger prints from one of the 13 package bombs recovered so far, which was matched with the DNA samples.

Wray described these explosives in the package bombs as IED (improvised explosive device), something which is normally used by terrorist groups in countries such as Afghanistan. These package bombs were transported to the FBI lab in Quantico, Virginia.

"This is dangerous and highly skilled, specialised work that requires great care," Wray said. He, however, refused to disclose anything about Sayoc's background or motives observing that this is an ongoing investigation.

Sessions said that over the past week, more than a dozen suspicious packages have been sent through the United States Postal Service to a media outlet, a Hollywood actor and at least seven high-ranking current and former political leaders in the Democratic Party.

Since Monday, homemade bombs and other suspected explosive devices have been addressed to Obama, Clinton, Hollywood actor Robert De Niro and a slew of figures disliked by the president's supporters.

"This is utterly unacceptable," Sessions said.

"Political violence or the threat of violence is antithetical to our vigorous system of self-government. It is a threat to that respect for law and process that allows our people to accept legislation, elections, court rulings with which they do not agree," he said.

Wray told reporters that 13 IEDs were sent to various individuals across the country.

Each device consisted of roughly six inches of PVC pipe, a small clock, a battery, some wiring and what is known as energetic material, which is essentially potential explosives and material that give off heat and energy through a reaction to heat, shock, or friction, he said.

While FBI agencies are still analyzing the devices in its laboratory, Wray said these are not hoax devices.

Giving details of the investigations so far, Wray said that based on their initial analysis, investigators uncovered a latent fingerprint from one of the envelopes containing an IED that had been sent to Congresswoman Maxine Waters.

"We have confirmed this fingerprint is that of Cesar Sayoc. There is also a possible DNA connection between samples collected from pieces of two different IED's mailed in separate envelopes and a sample previously collected from Sayoc in connection with an earlier arrest down in Florida," he said.

At the same time, Wray warned that there could be more such devices.

"Today's arrest doesn't mean we're all out of the woods. There may be other packages in transit now," he said.

For his part, Trump said he has instructed authorities to spare no resource or expense in finding those responsible, and bringing them to swift and certain justice.

"And we will prosecute them, him, her -- whoever it may be to the fullest extent of the law," he said.