Officials in Washington are investigating nearly 20 fraudulent mail-in ballots cast in the 2020 general election.

Authorities from the King County Prosecuting Attorney’s Office and the Federal Bureau of Investigation (FBI) are investigating the ballots believed to have been filed under the names of deceased individuals. The Washington Secretary of State is also involved in the case.

Of the 17 ballots flagged for fraudulent activity, eight were caught by election officials in November and nine more were discovered in January.