The Colorado Secretary of State’s Office took the unusual step Wednesday of issuing an order declaring that four people living in a small Gunnison County town are legal residents and properly registered to vote.

It stems from a controversy in which voters in the town of Pitkin alleged the district attorney’s office went to extraordinary lengths in an attempt to prove voters were ineligible to cast ballots, according to the secretary of state’s office.

Reports from residents included investigators entering properties to photograph homes, issuing subpoenas to monitor utility usage and encouraging residents to keep ledgers about their neighbors’ activities, according to a letter Deputy Secretary of State Suzanne Staiert sent Wednesday to 7th Judicial District Attorney Dan Hotsenpiller.

The state office opened an investigation after receiving complaints and heard “several troubling stories from voters,” according to the letter.

The order names four voters and applies to any others that may be in similar situations.

“Because your office refused to release a single record related to prior challenges and investigations, I was unable to determine how many voters you have targeted,” Staiert wrote, adding that more voters may be added to the order.

“My top priority as secretary of state is to ensure that every Coloradan can exercise his or her right to vote,” Secretary of State Wayne Williams said in a statement. “No amount of intimidation or voter suppression will be tolerated.”

In an interview, Hotsenpiller said he had not read the letter yet but stressed there was “certainly no inappropriate conduct by anybody” in his office.

He said his office has prosecuted seven people with misdemeanors in Gunnison County for violations of voter laws stemming from a 2016 municipal election. Six pleaded guilty and received deferred judgments and community service. A seventh defendant had a two-day trial and was found guilty.

“I don’t have any idea what is going on with the secretary of state’s office,” Hotsenpiller said, adding that the prosecution doesn’t impact the outcome of elections or whether a person can vote. “Any allegations that anyone associated with my office or myself have some kind of political motive or other motive regarding voting rights is puzzling because we don’t control that.”

The secretary of state has forwarded the issue to the U.S. Attorney’s Office in Colorado for further investigation. Hotsenpiller said he welcomes “any inquiry and any assistance or guidance from the U.S. Attorney’s Office.”

Jeff Dorschner, a spokesman for the U.S. Attorney’s Office in Denver, confirmed officials had received the information and declined further comment.