Suspected explosive devices were sent to former Secretary of State Hillary Clinton and former US President Barack Obama, the US Secret Service has said.
It comes two days after a bomb was found at the home of liberal philanthropist and financier George Soros in the suburbs of New York City.
The devices were discovered by technicians who screen mail sent to the former US officials.
The Time Warner building in New York was also evacuated due to a package.
CNN, which is located in the Time Warner building, reported that it evacuated its newsroom over a suspicious package.
According to a statement from the US Secret Service, the first package was addressed to
"Early this morning, October 24, 2018, a second package addressed to the residence of Former President Barack Obama was intercepted by Secret Service personnel in Washington, DC," the statement adds.
"Both packages were intercepted prior to being delivered to their intended location. The protectees did not receive the packages nor were they at risk of receiving them."
A US official told the Associated Press that a "functional explosive device" was found during a screening of mail sent to the home of
The FBI in New York said they were aware of the suspected packages, and are aiding in the investigation.
A spokeswoman for
The suspected explosive devices come two days after a confirmed pipe bomb was discovered in a mailbox at the home of
Explosive device found in Soros post box
Officials "proactively detonated" the device, and determined that it contained explosive powder and "had the components of a bomb".
White House spokeswoman Sarah Sanders condemned the "attempted violent attacks" against the public figures.
"The United States Secret Service and other law enforcement agencies are investigating and will take all appropriate actions to protect anyone threatened by these cowards," she said.