OKLAHOMA CITY - In an effort to clean up voter rolls, The State Election Board is sending letters to thousands of Oklahomans asking them to confirm their addresses or face being removed from the rolls by 2022.

According to the State Election Board, The letters won't be sent to every Oklahoman, only those who meet specific criteria. Some of the criteria includes voters who may be double registered after moving, some the board has been unable to contact, or some voters who haven't voted since 2016.

The letters have already been mailed to Canadian County, which was considered the test county according to the board’s spokesperson Misha Mohr. Letters will be sent to Washington county beginning this week. The state’s most populous counties Oklahoma, Cleveland and Tulsa counties will be next and then eventually every county will receive letters.

Anyone who gets one of these letters has 60 days to return the voter card in the letter or use the state's online voter tool.

Civil Rights advocates say targeting voters based on inactivity could unnecessarily remove eligible voters from the rolls or could punish rural or poor voters who may not have access to the internet.

"I also have a legal responsibility to maintain clean voter rolls to protect against those who would attempt to harm our democracy by using outdated voter lists to tamper with our elections,” State Election Board Secretary Paul Ziriax said in a statement.

Oklahoma was targeted by Russian hackers in 2016 but state officials say there was never a breach.

The Board of Elections must send all of the voter confirmation letters out by June 1 in order to be up to date for the 2020 elections.