KENOSHA, Wis. (AP) _ Anthrax scares shut down a middle school and a social services building Tuesday _ one day after an anthrax hoax at a Milwaukee family-planning clinic.

The FBI was investigating the threats.

Bullen Middle School was evacuated after receiving a letter purportedly contaminated with anthrax, a deadly livestock disease that can be transmitted to humans.

A similar letter was received at the Children's Social Services of Wisconsin building.

As a precaution, 33 people underwent decontamination procedures at the scene and were taken to a hospital for further cleansing and evaluation.

Dr. Gary Zaid, director of emergency medicine at Kenosha Hospital Medical Center, said all indications were that the threats were hoaxes.