The top two executives at NBC News tried to quell any in-house suspicions on Friday concerning their handling of Matt Lauer, the longtime “Today” show star who was fired on Tuesday.

Their communications with staff members came after competing media organizations had expressed skepticism about the official NBC denial. The network had said on Wednesday that its executive ranks had not been aware of Mr. Lauer’s alleged sexual misconduct involving female colleagues until they had learned of a detailed complaint on Monday.

Noah Oppenheim, the news division’s president, met with “NBC Nightly News” staff members at their daily meeting to tell them about recent conversations that took place between Mr. Lauer and NBC News executives.

According to an NBC employee who was present at the meeting and spoke about it on condition of anonymity to discuss internal issues, Mr. Oppenheim said that four executives — including himself and Andrew Lack, the NBC News chairman — had asked Mr. Lauer repeatedly in recent weeks if he had engaged in inappropriate behavior with staff members and that he had denied any wrongdoing.