HOUSTON (CBSDFW.COM/AP) — A spokeswoman for Sen. Ted Cruz says a package addressed to Cruz’s Houston campaign headquarters caused a lockdown. Authorities later lifted an evacuation order after saying two people were apparently exposed to a “white powdery substance.”

The Houston Fire Department tweeted Tuesday that tests for hazardous substances were negative after the building floor where Cruz’s office is located was evacuated.

The building is located in the 3200 block of Southwest Freeway. The fire department said the ninth floor of Phoenix Tower was evacuated.

Cruz spokeswoman Catherine Frazier says no one from the campaign staff was taken to the hospital.

Frazier said the package was opened in the lobby. She said authorities locked down the lobby and elevator for a couple hours.

It comes on the same day that authorities at the Pentagon say they found at least two packages believed to contain ricin, a deadly white powdery poison made from castor beans.

(© Copyright 2018 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)