Dallas Fire-Rescue says a white powder found inside an envelope at the Earle Cabell Federal Building Tuesday was harmless chalk.

DFR's hazmat team was called to the 14th floor of the building at 1100 Commerce Street just before 9:30 a.m. after the powder was reported.

Jason Evans, with DFR, said two people were isolated after coming into contact with the envelope and were evaluated by EMTs. They were OK and were released at the scene.

The rest of the building remained open and was not evacuated.

By 11 a.m. all DFR units had been cleared from the scene.

The Earle Cabell Federal Building houses district courts, bankruptcy courts, passport offices, the United States Attorney's office and Homeland Security, among other federal offices.

NBC 5's Jeff Smith contributed to this report.