IATSE Grips Local 80 closed its offices in Burbank today after receiving a threatening letter. “Local 80 received a letter threatening harm to our employees,” the local said in an email to members. “Burbank police have been notified, and an officer came to assess.

“They are currently evaluating the situation for credibility. We have evacuated our building out of an abundance of caution. The Local is closed until further notice.”

Burbank Police Sgt. Stephen Turner said in a statement that “Burbank PD is aware and detectives are investigating the credibility and validity of the threat.  No arrests have been made.  IATSE, in an abundance of caution, have closed their offices.”

The identity of the letter-writer is known by the police.

Dejon Ellis, Jr., the local’s business manager, could not be reached for comment, but he told Variety that the sender appeared to be distraught over the ongoing writer and actor strikes. “He said some very scary things. He’s just mad. He says he’s out of work and homeless. He’s distraught. I don’t know if it’s a cry for help or not knowing how to control his anger.”