Colorado Secretary of State

Tens of thousands of voters in Colorado and five other swing states appear to have been illegally removed from voter registration lists or prevented from registering, according to the New York Times.

Colorado appears to have violated a federal law prohibiting states from removing voters from the rolls within 90 days of a federal election unless voters die, notify the state that they have moved out of state, or are declared unfit to vote, the Times reported.

The state of Colorado removed about 37,000 people from voting rolls in the three weeks after July 21, the Times reported. But in that time, about 5,100 Coloradans moved out of state, and about 2,400 died, according to the Times.