Suspicious packages were sent this week to election offices in more than 20 states, leading to an FBI investigation, triggering evacuations and rattling staff, according to a CNN survey of state offices and Associated Press reporting.

Mississippi Secretary of State Michael Watson's office on Monday received a "suspicious package" that was promptly handed off to authorities before being opened.

A 'suspicious package' was sent to the California secretary of state headquarters in Sacramento, officials confirmed on Thursday. The announcement comes the same week the FBI said it was investigating the origin of suspicious packages sent to or received by election officials in more than 15 states.