Issues related to sexual harassment continued to plague 21st Century Fox as its Fox Business Network subsidiary confirmed on Thursday that it had suspended a longtime anchor, Charles Payne, pending an investigation into his conduct.

The development came exactly a year after a sexual harassment scandal at Fox News first burst into public view with a lawsuit against Roger E. Ailes, the network’s former chairman. As claims of widespread harassment continued to surface, 21st Century Fox has tried to clean house, ousting Mr. Ailes, the former star Bill O’Reilly and several other employees.

The suspension of Mr. Payne came after The National Enquirer published an article on Wednesday in which he acknowledged and apologized for an extramarital affair with a former CNN and Fox News contributor. That woman made claims of misconduct against Mr. Payne to lawyers for Fox, according to a person briefed on the matter.

“We take issues of this nature extremely seriously and have a zero-tolerance policy for any professional misconduct,” a spokeswoman for Fox Business said in a statement. “This matter is being thoroughly investigated and we are taking all of the appropriate steps to reach a resolution in a timely manner.”