This story was updated at 10:40 a.m. ET.

Priceline Group Inc. said Thursday its chief executive, Darren Huston, has resigned, effective immediately, following an investigation related to a personal relationship that he had with an employee that violated the company's code of conduct.

The travel website operator said Huston, who has been the company's CEO since January 2014, had acknowledged his misconduct and expressed regret.

"This did not involve issues about the company's financial statements, accounting or internal controls over financial reporting," Leslie Cafferty, a company spokeswoman, told Reuters in an email.

Huston will not receive any severance payments, the company said in a regulatory filing. The company appointed former CEO and current chairman Jeffery Boyd as interim CEO while the board conducts a search to name a successor.

Priceline said Huston resigned following an investigation overseen by independent members of the board of directors of the facts and circumstances surrounding a personal relationship that he had with an employee who was not under his direct supervision.

The investigation determined that “Mr. Huston had acted contrary to the company's Code of Conduct and had engaged in activities inconsistent with the board's expectations for executive conduct, which Mr. Huston acknowledged and for which he expressed regret,” a company statement said.

Huston's resignation comes just days before the company is scheduled to report its second-quarter results on May 4.

Data from Reuters were used to report this story.