Staff at the newspaper reportedly made a request on Monday for credentials to cover the Iowa Republican’s election event the following day. At the event, King, the incumbent, is expected to address supporters after voting results come in.

King’s campaign denied the paper’s reporter credentials to the event, the Register reported.

King’s office did not immediately respond to a request for comment.

Carol Hunter, the executive editor for the paper, told CNN Business that some of the paper’s staff will show up to the venue, but will leave if they’re sent away.

“The Des Moines Register will continue doing everything in its power to cover Rep. King fairly,” Hunter told CNN. “This decision is unfortunate because it not only shuts out the Des Moines Register reporter, but also the people of Iowa.”

King is vying for reelection for a ninth term in Congress. The incumbent is facing off against Democrat J.D. Scholten. King recently lost GOP support and corporate donors after endorsing a white supremacist for Toronto mayor.

The Des Moines Register, Iowa’s biggest newspaper, said it has had a tense relationship with King’s office for years. The publication compared the King campaign’s move to keep reporters out as similar to one in 2015, in which newspaper staff was kept out of a campaign event for Donald Trump, after the paper’s editorial board called on him to withdraw from the race.