FBI agents used DNA and a fingerprint to identify the Florida man suspected of sending at least 14 bombs to critics of U.S. President Donald Trump days ahead of congressional elections.
Cesar Sayoc has been charged with five federal crimes including threats against former presidents and faces up to 48 years in prison if found guilty, U.S. Attorney General Jeff Sessions said. He earlier said the suspect could face 58 years.
"We will not tolerate such lawlessness, especially political violence," he said.
Authorities are still investigating whether other people were involved and did not rule out the possibility of further arrests or more explosive devices in the mail.
FBI agents arrested Sayoc, 56, in Plantation, Florida and also hauled away a white van plastered with pro-Trump stickers, the slogan "CNN SUCKS" and images of Democratic figures with red crosshairs over their faces.
FBI Director Christopher Wray told the news conference that fingerprints on a package sent to Representative Maxine Waters belonged to Sayoc.
He also said there could be other packages.
Announcing the arrest by the Federal Bureau of Investigation to a cheering audience at the White House, Trump said such "terrorizing acts" were despicable and had no place in the United States.
"We must never allow political violence to take root in America - cannot let it happen," Trump said. "And I'm committed to doing everything in my power as president to stop it and to stop it now."
Sayoc's home address was listed in public records as an upscale gated apartment complex in the seaside town of Aventura, Florida.
According to the records, he is a registered Republican with a lengthy criminal past - including once making a bomb threat - and a history of posting inflammatory broadsides on social media against Trump's political foes.
Sayoc was being held at an FBI processing centre in Miramar, Florida, CNN said. He was expected to be taken to the Federal Detention Center in downtown Miami and will likely make his first appearance before a judge on Monday, according to former Assistant U.S. Attorney David Weinstein.
A federal law enforcement source said charges would likely be brought by federal prosecutors in Manhattan and Sayoc transferred to New York City.
Four more suspicious packages were found on Friday, according to officials and media reports, bringing the total to 14. None of the devices has detonated, and no injuries have been reported.
The intended recipients of packages discovered on Friday included Democratic U.S. Senator Cory Booker of New Jersey, former U.S. Director of National Intelligence James Clapper, Democratic U.S. Senator Kamala Harris of California and Democratic donor Tom Steyer.
'STOP THE RANCOUR'
Hours after a federal law enforcement official said the investigation's focus on Florida had intensified, police closed roads around the parking lot of an AutoZone store in Plantation where Sayoc was arrested, and helicopters flew overhead.
Investigators covered Sayoc's van with a blue tarp before removing it on a truck.
All the people targeted by the suspicious packages have been maligned by right-wing critics. Packages that surfaced earlier in the week were addressed to Obama, former Vice President Joe Biden, former Secretary of State and presidential candidate Hillary Clinton, billionaire Democratic Party donor George Soros, Representative Maxine Waters, former Attorney General Eric Holder, former CIA director John Brennan and actor Robert De Niro.
Trump's critics charged that his inflammatory rhetoric against Democrats and the press created a climate for politically motivated violence. Tensions are running high ahead of Nov. 6 elections that could shift the balance of power in Congress, which is currently controlled by Trump's fellow Republicans.
"If we don't stop this political mania, this fervour, rancour, hatred, you'll see this again and again and again," New York Governor Andrew Cuomo told MSNBC. "We have to get to the genesis, and the genesis is an overheated, vitriolic political division in this country and it starts with the leaders, and it starts with the president."
Trump's supporters accused Democrats of unfairly suggesting the president was to blame for the bomb scare.
After first calling for unity at the White House event, Trump lamented attacks against him and again pointed at the media.
"I get attacked all the time ... I can do the greatest thing for our country, and on the networks and on different things it will show bad," he told the crowd, acknowledging an attendee who shouted "fake news."
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
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