COLUMBUS, Ohio -- A package exploded late Tuesday night near Port Columbus International Airport, causing evacuations and exposing some to the West Nile virus.

The incident occurred shortly before 10:30 p.m. at a FedEx facility on Citygate Drive, Columbus television station WCMH-TV reported.

Columbus fire officials said that the package, which contained brain matter from birds that had tested positive for the West Nile Virus, was mailed from the Ohio Department of Health.

The package was to be shipped to the University of Texas department of pathology in Austin, Tex.

The shoebox-sized package exploded, or opened up, inside of the Fed-Ex building, the television station reported.

Columbus police, the bomb squad, and the Columbus fire hazardous materials team were called to the scene.

Approximately 50 employees were evacuated from the building. Nearby businesses were also evacuated.

"This is not terrorist-related," Columbus Police Sgt. Brent Mull said. "This was something that was shipped legally and properly."

No injuries were reported. The package was properly labeled and the virus was dead in the brain matter, according to the Ohio Department of Health.

Officials said that the material was no longer infectious and was never a threat to anyone's health.