It shall be unlawful for any member of a criminal street gang to willfully threaten to commit a crime which will result in death or great bodily injury to another person, with the specific intent that the statement is to be taken as a threat, even if there is not intent of actually carrying it out, which, on its face and under the circumstances in which it is made, is so unequivocal, unconditional, immediate, and specific as to convey to the person threatened a gravity of purpose and an immediate prospect of execution. (Code 1979, § 27-174)