WASHINGTON (AP) — A series of bomb threats across multiple battleground states and baseless claims of wrongdoing by former President Donald Trump disrupted an otherwise smooth Election Day that capped a tumultuous presidential campaign.

From the polling place to the courtroom, ABC News tracks the latest election security developments as experts warn about the spread of misinformation and disinformation from within the U.S. and abroad.

A man at the U.S. Capitol was arrested and several stated received bomb threats that were deemed non-credible, according to authorities.

Threats lead to temporary polling station closures in Georgia, Arizona, Pennsylvania; Russian embassy responds

Vice President Kamala Harris visited a Puerto Rican restaurant in Reading, Pennsylvania, Monday night, accompanied by the state's governor, Josh Shapiro, and Rep. Alexandria Ocasio-Cortez of New York. He called that a "secret weapon for us" and said that volunteers were "knocking on 2,000 doors a minute in Pennsylvania over the weekend."

The FBI says Russian actors may have been behind dozens of false bomb threats targeting voting centres in swing states.

Officials are on guard for equipment failures and software issues – as well as violent threats that have infected the democratic process.

Two polling stations had been evacuated in Union City and Fulton County due to the threats on Tuesday. Secretary Brad Raffensperger said officials were investigating but they do not believe they were viable.