State officials on Tuesday acknowledged widespread errors in their list of 95,000 Texas voters flagged as potential non-citizens, reinforcing the concerns of advocates who say the state’s effort amounts to illegal voter suppression.

In Harris County alone, officials said, more than 60 percent of nearly 30,000 names on a list the state supplied last week are being removed after new guidance from state officials. Voter registrars in several other counties reported getting similar calls Tuesday from the Texas Secretary of State’s office, which last week said its review showed that 95,000 registered voters did not appear to be U.S. citizens.

Meanwhile on Tuesday, the League of United Latin American Citizens sued Secretary of State David Whitley and Attorney General Ken Paxton, asking for data used to develop the original list. The disclosure that many of those on the state’s list had been found to be U.S. citizens intensified the concerns that prompted the suit.

The lawsuit accuses Whitley and Paxton of violating federal election laws. It says the initiative, announced last week by Paxton and Whitley’s office, is a method of voter suppression seen around the country and a “witch hunt” meant to instill fear primarily in Hispanic voters.

“That’s all they’re doing,” said Luis Vera, LULAC’s national general counsel. “They’ve done it in Florida; they’ve done it in Arizona and other states. It’s voter intimidation, voter threats.”

Zenén Pérez, the advocacy and communications director for the Texas Civil Rights Project. said the secretary of state’s office should rescind the entire advisory.

In announcing the list last week, Whitley and Paxton hailed the effort as part of a fight against fraudulent voting. Conservative Texas leaders, along with President Donald Trump, have alleged that illegal voting and voter fraud are serious problems that justify voter identification laws and other policies seen by advocates as voter suppression strategies.

In response to reports about the removal of names from the state’s list, the secretary of state’s office said in an emailed statement that it was “continuing to provide information to the counties 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 read.

On Tuesday, officials in Harris County and several other counties were told to remove from their lists names of people who registered to vote at Texas Department of Public Safety offices. Harris County officials also were advised to remove those who registered to vote at a naturalization ceremony, said Douglas Ray, a special assistant county attorney who specializes in election issues.

With the new criteria, Harris County was able to remove more than 60 percent of the names off the nearly 30,000-voter list it was sent. Only about 11,000 names remain.

“Our experience with these mass lists from the secretary of state’s office is that they’re very questionable, so we have to treat them very carefully,” Ray said.

Cheryl Johnson, Galveston county's tax assessor-collector, said her office started sending letters Monday asking people on the list to verify their citizenship or risk expulsion from voter rolls. But on Tuesday, Johnson said, the secretary of state's office notified her that some on the list had been verified as citizens.

"We managed to retrieve the second batch of letters that we were going to mail today," said Johnson. "The ones we sent yesterday, we're going to go back and check those."

Johnson said 837 Galveston County voters were flagged by the state, and her office sent letters to 92 registered voters on Monday with plans to mail more on subsequent days. The letters ask that the recipients provide a U.S. passport, birth certificate or citizenship papers to her office within 30 days, she said.

Johnson said she realized by Tuesday afternoon that more than half of the letters sent Monday matched a source code the secretary of state’s office said to check. She plans to send a letter to those affected on Wednesday. Ten letters that were supposed to be mailed out on Tuesday were also pulled, but her office still planned to send out 77 letters to registered voters in the area.

"We're not going to infringe on anybody's right to be a registered voter," Johnson said. "What we are trying to do is ensure the integrity of the voter roll for all citizens of Texas and all the citizens and voters in my county."

In Fort Bend County, John Oldham, elections administrator, said roughly 8,035 voters in his county were flagged by the Secretary of State's office. But in a call Tuesday morning, Oldham said, his office was advised not to send letters to those on the list "until you review a little more."

The secretary of state's office mentioned the same DPS code issue explained to other county voting officials, Oldham said. He said his office would thoroughly review each flagged voter's record before sending any letters.

Travis County registrar Bruce Elfant said he was confident that the list of 4,500 voters his county received “will drop by a significant amount” after review. Bexar County officials said the lawsuit had a freezing effect on any action they might take on the issue.

In Waller County, Christy Eason, the elections administrator, had also not sent out any letters to potentially ineligible voters yet. She said the secretary of state’s office advised her office Tuesday to check for names with the DPS source code.

"We'll definitely be very proactive about it and probably do more so than is required to do to make sure that we're not canceling someone that clearly should be registered," said Eason.

Authorities in Jefferson, Orange and Hardin counties each confirmed that they had received notice from the state that some of the flagged voters did not belong on the list of potential noncitizens. About 300 people had been flagged in Jefferson County and fewer than 100 in Orange County.

Voter registration officials in Collin and Williamson Counties got similar calls Tuesday from the secretary of state's office, the Texas Tribune reported.

Reporters Guillermo Contreras, Dylan McGuinness and Erica Apodaca contributed.