First a guy shoots his TV over Bristol Palin's fancy footwork. Now, another viewer is apparently taking America's favorite ballroom-dance extravaganza way too seriously.

Emergency responders in Los Angeles were called to the offices of 'Dancing with the Stars' late Friday to investigate a white powder that was reportedly contained in a piece of fan mail addressed to Sarah Palin's daughter, the 20-year-old Alaskan who has remained in competition with 'DWTS' partner Mark Ballos despite poorly judged performances.

The FBI told TMZ, "The L.A.P.D., L.A. City and FBI Hazardous Materials officials responded to a report of a threatening letter containing white powder."

The alarming incident resulted in a section of the studio being evacuated, according to a source.

ABC said in a statement, "Security and the Los Angeles Fire Department and Los Angeles Police Department were immediately notified....Measures were taken to secure the area and ensure the safety of personnel. Ultimately, we were advised by the LAFD that the substance was determined to be talcum powder."