Several Alabama post office employees on Tuesday were sickened after a parcel's contents leaked and taken to the hospital.

The substance reportedly was fish bait, U.S. Postal Service spokesman Gerry McKiernan said. Witnesses described a strong odor similar to that of garlic and said the package's contents stained the floor and caused some workers to throw up and have headaches; six were hospitalized, according to FOX News affiliate WBRC.

The employees were expected to return to work, McKiernan said.

The Hueytown Fire Department sent a hazardous materials team to the post office, a few miles west of Birmingham.

The six were taken to UAB Medical West in Bessemer, hospital spokeswoman Haley Tingle said.

"They are being decontaminated, but I don't know more than that," she said.

The Associated Press contributed to this report.