The devices were "immediately identified during routine mail screening procedures" and "were appropriately handled as such," the Secret Service said in a statement . Obama and Clinton "did not receive the packages nor were they at risk of receiving them," according to the agency.

Separately, the Time Warner building in New York City was evacuated after reports of a suspicious package to CNN.

"We are working with authorities to determine the severity of the situation," CNN president Jeff Zucker said in a memo to staff after his network's anchors had to leave their studio to broadcast from the streets outside their building after an alarm went off on air.

"We are also checking all bureaus around the world, out of a complete abundance of caution," Zucker said.

ADVERTISEMENT

Two other suspicious packages were reported later in the day.

"A device has been sent to my office in Manhattan, which we were just informed about, and that device is also being handled,” Cuomo said at a press conference that included New York City Mayor Bill de Blasio and New York Police Department commissioner James P. O'Neill.

Later reports from the Associated Press and other sources, however, said that the package sent to Cuomo was not a bomb and was unrelated to the other packages.

The threatening packages come weeks before the midterm elections and at a time of historic political polarization in the United States, with each major political party blaming the other for riling up supporters to the point of rage.

The packages sent to the Clintons, Obamas and CNN appeared to have similarities, according to authorities, who seemed to be investigating whether they were sent by the same person.

The Secret Service said one package intercepted late Tuesday was addressed to Hillary Clinton, who was President Trump's Democratic opponent in the 2016 presidential election. The package addressed to Obama was found early Wednesday morning.

The statement said the agency "has initiated a full scope criminal investigation that will leverage all available federal, state, and local resources to determine the source of the packages and identify those responsible."

The FBI said it activated its Joint Terrorism Task Force to assist with the investigation, but declined to comment further.

The White House condemned the attempted bombings and pledged that federal law enforcement "will take all appropriate actions to protect anyone threatened by these cowards."