YORK COUNTY, Pa. (WHTM) — The York County Office of Elections and Voter Registration says duplicate mail-in ballots were accidentally sent to hundreds of York County residents.

The office said due to a clerical error, the duplicate mail-in ballots were sent to 400 York County residents. The office said that they are in the process of contacting all voters who have been affected and providing instructions on how to destroy or surrender any duplicate ballot received.

The office states that they recognize the significance of the error and continue to have multiple processes in place to ensure no voter can submit two votes, regardless of any duplicate ballots received.

Any evidence suggesting an individual has or attempted to cast more than one vote will be referred to the York County District Attorney’s office for investigation.

The office further stated they will continue to review and revise their internal processes to prevent this from happening again in the future.