Scientology facilities were evacuated and temporarily closed Wednesday and Brand Boulevard in Glendale, Calif., was closed for two hours after a Scientology church there received one of the suspicious mailings, the Los Angeles Times reported.
"Initial field testing by LAPD indicates the powder is harmless. However, further testing will be conducted. We will also work to assess what threat, if any, was associated with the mailings and determine whether any federal statutes were violated," FBI spokeswoman Laura Eimiller said.
Officials said the mailings were probably a hoax and tests revealed the powder to be wheat germ and cornstarch. The incident hasn't been proved as having a connection to an Internet hacking attack last week on the Church of Scientology Web site, the Times said.