Mysterious White Powder Sent to 'Dancing With the Stars' Studio

A Dancing With the Stars staff member discovered an envelope containing a mysterious white powder and a threatening letter at the show's production offices.

Though the white powder was eventually determined to be harmless, the scare led to the evacuation of the studio.

"Measures were taken to secure the area and ensure the safety of personnel," ABC spokeswoman Amy Astley said. "Ultimately we were advised by the LAFD that the substance was determined to be talcum powder."

Los Angeles city hazardous materials officials, Los Angeles Fire Department, Los Angeles Police Department and the FBI immediately responded to the CBS Studios, where the show is filmed.

Immediate tests cleared the envelope for hazardous materials, and the envelope has now been sent to a regional lab for further testing. The FBI and LAPD are conducting a joint investigation.

The gossip site TMZ.com is reporting that the letter was targeting Bristol Palin, though authorities have neither confirmed nor denied this.

The FBI would not confirm the intended recipient of the letter to ABC News.

This season of the show has made headlines as fans have complained that Palin, the daughter of Sarah Palin, has advanced to the finals because her mother's supporters are manipulating the voting. Palin has remained on the show, despite consistently landing at the bottom of the judges' leader board.

This is hardly the first instance of a fan targeting a contestant on the hit show.

In 2009, Olympic gymnast Shawn Johnson was stalked by an obsessed fan who drove from Florida to California, attempted to climb the fence to get into the studio. He was quickly arrested, and police found guns and duct tape in his car.

Should be an interesting weekend and next week on the DWTS set.