Authorities said testing of a powder found in a letter opened Monday at a T.W. Alexander Drive office building determined it was not hazardous.
Sheriff’s investigators were working to find out who sent the letter and why, however, the sheriff’s office said.
The powder was in a letter opened in a room at 10 T.W. Alexander Drive.
The letter was addressed to the N.C. State Education Assistance Authority, sheriff’s office spokeswoman Tamara Gibbs said, but it also had a name of someone who does not work there.
The area where the powder was found was secured while experts worked, and there were no reports of injuries or illness.
The sheriff’s office called in the city’s Bio-Chemical Emergency Response Team, a group of officers with special training and equipment for dealing with hazardous substances.
In addition to NCSEAC, the building in Research Triangle Park houses the College Founation of North Carolina, UNC-TV headquarters and a Bright Horizons daycare center, according to that company’s website.