Barnes & Noble fired its chief executive, Demos Parneros, for violating the company’s policies, the company said on Tuesday without specifying the policies.

Mr. Parneros was not terminated because of “any disagreement with the company regarding its financial reporting, policies or practices or any potential fraud relating thereto,” Barnes & Noble said in a statement.

The company added that he would not receive any severance payment and that he had been removed from the board.

Mr. Parneros is the company’s fourth chief executive to depart in five years. He had been in his role for just over a year, having risen to the position from the role of chief operating officer to replace Ronald Boire. Mr. Boire had spent less than a year as chief executive before being ousted in August 2016 after board members decided he was “not a good fit for the company.”