The FBI says a possible hazardous material that prompted the evacuation of a Minneapolis apartment complex and injured a University of Minnesota student could be ricin.

The FBI says test results "indicated the presumptive potential presence of ricin" in substance found in the Minneapolis apartment.

On Tuesday, a person was hospitalized after "unconfirmed reports of ricin" at the Dinkytown apartment building, according to the Minneapolis Fire Department. 

The FBI also says the female student "may have been intentionally handling the material." The student remains hospitalized.    

RELATED: Fire officials: 1 hospitalized after 'unconfirmed report of ricin' in Minneapolis

Emergency crews were called Tuesday to The Marshall, at 515 14th Avenue SE, a 316-unit complex that caters to students at the nearby university. The complex was evacuated but residents were allowed to return after authorities determined there was no danger to the public.

"Central to the ongoing FBI investigation is how the female who went to the hospital came into contact with this potentially dangerous material. Early indications from the ongoing investigation reveal the female likely did not come into contact with the material in a random fashion; meaning she may have been intentionally handling the material. Given this early information and the ongoing investigation, we do not believe the general public is at risk at this time given the likelihood the material was confined to the single apartment in question and that it was likely not being used for any criminal activity," according to a news release.

Ricin is a poison found naturally in castor beans. The FBI says evidence will be sent to the bureau's lab in Virginia for positive identification.