Some registered to vote when they applied for a driver’s license at the Texas Department of Public Safety, which requires them to prove citizenship status to state officials. Others registered at naturalization ceremonies, a data point to which state officials said they did not have access.

Election officials in Harris County, home to Houston, said they received 30,000 names — the largest single batch of potential noncitizen voters — from the secretary of state’s office Monday. By Tuesday afternoon, they had determined that roughly 400 of those names were duplicates and 60 percent so far of the others were U.S. citizens.

“We are not willing to conclude at this point that we know of anybody on this list who is not a United States citizen,” said Douglas Ray, special assistant attorney for Harris County. “We may determine that at a later time, and we are going to investigate that very carefully, but as you can tell by the numbers, so far things ain’t looking good for this list,” referring to the state’s claim.

Local officials reported similar findings Tuesday in Fort Bend County, outside Houston; Travis County, home to the state capital, Austin; and Williamson County, outside Austin. All said they had been instructed by the secretary of state’s office Tuesday to disregard the names of voters who registered at state public-safety offices.

On Tuesday, the office of David Whitley, who was appointed secretary of state in December by Gov. Greg Abbott, said in a statement that it was continuing to work with local officials “to assist them in verifying eligibility of Texas voters.”

“This is to ensure that any registered voters who provided proof of citizenship at the time they registered to vote will not be required to provide proof of citizenship as part of the counties’ examination,” the statement said.

In an announcement Friday, Whitley’s office questioned the citizenship status of 95,000 voters. That finding grew out of an 11-month investigation by the secretary of state’s office and the Texas Department of Public Safety, which declined to comment Tuesday.

Attorney General Ken Paxton, a Republican who has zealously prosecuted individual cases of voter fraud, quickly amplified that announcement with a pledge to investigate the names on the list. A spokeswoman for his office did not respond to a request for comment Tuesday.

Democrats and voting-rights advocates expressed skepticism about the state’s claims last week, pointing to the possibility of administrative error as well as the state’s history of voter suppression.

Voter registration in many Texas counties is handled by the tax assessor, a holdover from the Jim Crow practice of collecting a poll tax, Ray said. Poll taxes were abolished by the 24th Amendment to the U.S. Constitution in 1964.

Kristen Clarke, the president of the Lawyers’ Committee for Civil Rights Under Law, called the problems that arose Tuesday “an unsurprising development.” She said Paxton had been “reckless and irresponsible to race forward with broad, sweeping allegations without conducting full, due diligence.”

Another group, the League of United Latin American Citizens, filed a federal lawsuit Tuesday that accused Paxton and Whitley of violating the federal Voting Rights Act.

Chris Davis, the President of the Texas Association of Elections Administrators and the elections administrator in Williamson County, said his office received a list of 2,067 names this week, including 34 duplicates. It began a “very methodical and very deliberate and careful” investigation into the remaining names and found many whose citizenship was not in question.

“We found some records where two things existed at once,” Davis said. “One was the DPS had identified them as potential noncitizens, but also these same people had registered to vote at the DPS and so had been verified to be citizens.”

Compounding problems for local officials is the fact that the so-called list is not actually a list.

John Oldham, the elections administrator in Fort Bend County, said four of his employees were combing through documents related to 8,035 people that his office received Monday.

In Travis County, Bruce Elfant, the tax assessor-collector and voter registrar, said his office was trying to organize the “jumble” of information it received on 4,500 voters into a usable format. He said that even a cursory review of the information they received turned up a “significant” number of people who the secretary of state has now told them to remove.

“I said to the secretary of state’s office this morning, ‘It would have been nice if you sent it in a spreadsheet,'” he said. “They told me, ‘Well, we didn’t.’ A lot of things would have been nice, I guess.”

This article originally appeared in The New York Times.