US President Donald Trump has called for unity after suspected explosive devices were mailed to broadcaster CNN and leading Democrats, including former president Barack Obama and the Clintons, saying acts of political violence have "no place" in the United States.
Former Democratic presidential candidate Hillary Clinton was among some of the most high-profile Democrats targeted with America bitterly divided ahead of November 6 elections - seen as a referendum on the Republican president.
The CNN bureau in New York also received a device looking like a pipe bomb, leading police to evacuate the building, and New York Governor Andrew Cuomo, a Democrat, said his office also received a suspicious package.
CNN is well known for its robust coverage of the Trump administration and is routinely singled out for harsh words by the president, who succeeded Mr Obama and defeated Ms Clinton in 2016.
Signs at his rallies regularly condemn the network.
“This clearly is an act of terror attempting to undermine our free press and leaders of this country through acts of violence,” New York Mayor Bill de Blasio told a news conference.
An NYPD Bomb Squad truck on West 58th St., outside CNN's Manhattan office. Source: AAP
The device sent to see CNN appeared to be a "live explosive," New York Police Commissioner James O'Neill said.
The package containing the device sent to CNN also had in it a suspicious powder, according to the NYPD.
A law enforcement official told CNN examination of all of the devices shows them to be constructed along similar lines, with at least one device containing projectiles such as shards of glass.
The devices are rudimentary but functional, CNN has reported.
"So far the devices have been what appear to be pipe bombs," FBI agent Bryan Paarmann said.
The spree of bomb alerts was kicked off Monday with a device found at the New York home of billionaire liberal donor George Soros.
Other targets included prominent African American Democrats - Mr Obama's former attorney general Eric Holder and Maxine Waters, a lawmaker from California - both outspoken Trump critics.
All the packages reportedly included the return address of Debbie Wasserman Schultz, former chairwoman of the Democratic National Committee.
A Bomb Squad technician in a bomb suit outside CNN’s New York office. Source: Robert Deutsch-USA TODAY/Sipa USA
A suspicious device sent to the Manhattan office of New York's Democratic Governor Andrew Cuomo turned out to be a false alarm, as did a scare in the offices of rising star Senator Kamala Harris.
Mr Trump, speaking from the White House, used his presidential perch to appeal for unity, saying acts of political violence have "no place" in the United States
Critics on the left accuse his rhetoric-laden presidency of emboldening right-wing extremists and condoning violence.
"At these times we have to unify and send one very clear and strong message that acts of political violence of any kind have no place in the United States of America," Mr Trump told an event on the opioid crisis.
First Lady Melania Trump opened the White House gathering by denouncing "cowardly attacks" and condemning "all who choose violence".
The packaging was addressed care of CNN to former CIA director John Brennan, who has worked as a television analyst but not for the channel.
The Secret Service intercepted the package addressed to Ms Clinton at the home she shares with her husband, former president Bill Clinton, north of Manhattan on Tuesday, and a second package addressed to Mr Obama's Washington home on Wednesday.
There has been no claim of responsibility and no one was yet thought to have been arrested.
