Suspected explosive devices were sent to former Secretary of State Hillary Clinton and former US President Barack Obama, according to the Secret Service.
It comes two days after a bomb was sent to the home of liberal philanthropist and financier George Soros at his home in the suburbs of New York City.
The devices were discovered by technicians who screen mail sent to the former US officials.
It was not immediately clear where the suspicious packages were found.
According to a statement from the US Secret Service, the first package recovered was addressed to Mrs Clinton late on 23 October.
“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.”
The FBI in New York said they were aware of the suspected packages, and are aiding in the investigation.