MARION COUNTY, Fla. -- Threats referencing the Sept. 11 terrorist attacks mailed to schools in Marion County prompted officials to ban backpacks and book bags on all public school campuses Tuesday.

Parents were notified late Monday via an automated telephone message by Marion County School Superintendent Jim Yancy.

"Several of our schools received written threats of violence in the mail targeting tomorrow, the anniversary of Sept. 11," Yancy said. "Law enforcement is investigating the threats and to help them we are not allowing backpacks or book bags."

Yancy also released another statement concerning the threats, saying, "We will have extra eyes and ears on every campus as a precaution. And finally parents please talk with your children about appropriate behavior."

All of the threats in Marion County were received on Monday.

Crime lab technicians are examining the written threats for any evidence that might lead detectives to the person responsible.

Anyone with information on the written threats is urged to call Crime Stoppers of Marion County at 368-STOP.

Agencies involved in the investigation include the Marion County Sheriff's Office, Ocala Police Department, Florida Department of Law Enforcement, the U.S. Postmaster, and the FBI.

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