HOUSTON - Reports say that two people have been taken to the hospital after being exposed to a powdery substance in a piece of mail at Senator Ted Cruz's campaign office in Houston.

ABC 13 reports that Cruz's office in the Phoenix Tower was cleared out by firefighters late Tuesday morning. The ninth floor of the building was evacuated, and the elevators were turned off as a precaution.

Two people were taken to the hospital after apparently being exposed to a white powdery substance in an office building at 3200 SW Fwy. The 9th floor of the Phoenix Tower has been evacuated as HFD HazMat is responding to the scene working to determine the nature of the substance.

— Houston Fire Dept (@HoustonFire) October 2, 2018

The fire department says the evacuation order was lifted after the space tested negative for hazardous substances.

Officials say the two people taken to the hospital are not affiliated with Cruz's campaign.