Executives at radio broadcaster Cumulus Media sent a strongly-worded memo to its radio hosts and station owners last week warning them to stop promoting conspiracy theories that the 2020 presidential election was rife with fraud.

The memo was sent on Wednesday, the same day that supporters of President Donald Trump stormed the U.S. Capitol building.

The memo was distributed to Cumulus employees in charge of talent and programming across the company, including at the broadcaster’s Westwood One division, which employs conservative talk show hosts Ben Shapiro, Dan Bongino and Mark Levin.

“We need to help induce national calm NOW,” the memo read. “Cumulus and Westwood One will not tolerate any suggestion that the election has not ended.”

The memo, written by Cumulus vice president Brian Philips, went on to say that any talent or other employee who continues to promote election-related conspiracy theories will lose their job.

“If you transgress this policy, you can expect to separate from the company immediately,” Philips wrote. “There will be no dog-whistle talk about stolen elections, civil wars or any other language that infers violent public disobedience is warranted, ever.”

Philips said the policy applies to its broadcast products as well as the company’s online presence, including websites and social media platforms.

Cumulus syndicates mostly-conservative talk and political affairs programing to hundreds of stations across the country through its Westwood One subsidiary. It also operates more than 400 local radio stations in 86 markets, including KABC (790 AM) in Los Angeles, KGO (810 AM) in San Francisco and KMJ (580 AM, 105.9 FM) in Fresno.