The powder was found in the mailroom for the ABC show ‘‘Dancing With the Stars,’’ which is staged on the lot at CBS. –File Photo

LOS ANGELES: The FBI says it is investigating the discovery of a threatening letter containing white powder that was received at CBS Studios in Los Angeles.

FBI spokeswoman Laura Eimiller says an initial screening indicates the substance was not hazardous, but the letter will be transported to a regional lab for further testing.

Eimiller says hazardous materials officials with the city of Los Angeles, Los Angeles police and the FBI responded to the studios Friday night.

Los Angeles Fire Department spokesman Brian Humphrey says firefighters also responded to the scene, but no one was treated for injuries.

KCAL-TV reports the powder was found in the mailroom for the ABC show ‘‘Dancing With the Stars,’’ which is staged on the lot at CBS. —AP