U.S. Rep. Jeff Van Drew is accusing New Jersey Governor Mikie Sherrill of responding to questions about New Jersey’s voter registration system with political attacks rather than providing answers about how thousands of people who identified themselves as noncitizens were placed on the state’s voter rolls.

Van Drew, a former Democrat who switched over to the Republican party several years ago, said in a statement that he and members of the Republican Study Committee initially sought information about the voter registration issue to determine how the system failed and what safeguards are in place to prevent similar problems in the future.

The congressman said New Jersey’s admission that thousands of people who identified themselves as noncitizens were registered to vote — and that some individuals registered through the error later cast ballots — warranted a thorough investigation.

“For years, those of us who raised concerns about the integrity of our voter rolls were dismissed as conspiracy theorists,” Van Drew said. “Then New Jersey admitted that thousands of individuals who said they were not citizens were registered to vote.”

Van Drew said his letter did not blame Sherrill for the problem, which he noted occurred under former Governor Phil Murphy’s administration. Instead, he said, the lawmakers asked how the registration error occurred, why existing safeguards failed to prevent it and what steps are being taken to ensure it does not happen again.

He accused Sherrill of failing to address those questions in her response.

“Instead of answering those questions, Governor Sherrill responded with Democratic talking points, attacks on President Trump, and personal attacks against me and the Republican Study Committee members who joined me in seeking answers,” Van Drew said.

Sherrill, a Democrat, has pushed back against Republican claims surrounding election integrity and has criticized efforts that she views as undermining confidence in New Jersey’s elections.

Van Drew said the issue should not be viewed as a partisan dispute.

“This was never about Governor Sherrill or any one political party,” he said. “It is about New Jersey and the integrity of our country’s elections.”

Van Drew said he and his Republican colleagues will continue seeking information about the voter registration error and will press state officials for accountability.

“Our mutual constituents deserve fair and secure elections, and they deserve the truth about how something this serious was allowed to happen,” he said. “We will not give up until the people of New Jersey get the answers they deserve.”