An investigation is underway after a series of suspicious packages sent to prominent Democrats have been found.

One package was found at Bill and Hillary Clinton’s home in Chappaqua, a New York City suburb, this morning, the Associated Press reports. The Secret Service says another suspicious package was sent to Barack Obama but intercepted in Washington, D.C. The device was sent by mail. The Secret Service has identified it as “a potential explosive device.”

Packages sent to former Presidents are routinely screened.

Officials tell The New York Times that the device sent to the Clintons is similar to the one sent to Obama and liberal philanthropist George Soros.