CHICAGO (CBS) — Three people were taken to hospitals Thursday morning, and several others reported feeling sick, after a suspicious package “emanating a foul odor” was found in an office building in the Loop.

Chicago Police Central District Cmdr. Michael Pigott said officers responded to a call of a suspicious package mailed to an office building at 131 S. Dearborn St. The package arrived at the building around 9 a.m. as part of normal mail delivery.

Out of precaution, police brought in bomb squads, Fire Department hazmat teams, Chicago Department of Environment crews, and the U.S. Postal Inspection Service to help investigate.

Pigott said building managers also evacuated the third floor as a precaution.

Fire Department officials said the package was “emanating a foul odor” when it was opened.

Police and fire officials said bomb squads tested the package, and found nothing dangerous or out of the ordinary. The package had a return address, and investigators have contacted the person who sent it.

“We do not think that this, at this point, is a criminal incident,” Pigott said.

According to Pigott, when the package was opened, “it emitted an odor,” but authorities do not believe it was harmful.

However, two people were taken to hospitals after complaining of breathing problems, and one other person was taken to the hospital for hypertension. At least 17 other people in the offices refused medical treatment.

“At this point, we don’t think there was anything out of the ordinary about this package, and most of this was just precaution,” Fire Department Deputy District Chief Michael Carbone said.