At least a dozen mailed ballots were intercepted and cast on the Western Slope before voters received them, according to the Colorado Secretary of State’s Office. Three of those ballots were cast and counted in Mesa County before the county clerk was able to pull them from the final tally.

Colorado’s Department of State learned about the intercepted ballots on Tuesday.

“The ballots were filled out, the return envelopes were signed, they were then returned to a USPS blue box, so that’s a postal box, not a ballot drop box,” said Secretary of State Jena Griswold in a news conference on Thursday afternoon. “The issue was discovered during the signature verification process.”