Okla. Stat. tit. 21, § 21-778: Threatened libel

Any person who threatens to publish a libel concerning any other

person, or concerning any relative, wife or child or dead relative

of such person, or member of his family, shall be liable civilly and

criminally to have the same intent as though the publication had

been made. But if the threat be not in writing, the threat and

character of the libelous matter must be proven by at least two

witnesses, or by one witness and corroborating circumstances.