Mailrooms at more than two dozen D.C. public schools received packages filled with a suspicious white powder this afternoon.

According to Pete Piringer, D.C. Fire and Emergency Medical Services spokesman, a series of schools reported receiving envelopes of an unidentified white substance beginning at 1 p.m. today.

“In all cases we’ve been able to run a battery of tests and have identified no toxic material or anything that represents an immediate safety issue,” he said in a recording on the D.C. Fire and EMS media hotline.

According to the statement, which was recorded at 3:45 p.m., between 12 and 15 schools across the city had reported incidents. A later statement recorded at 7:45 p.m. increased this number to 27. Additionally, a corrections facility in North East D.C. received a package similar to those sent to the public schools.

Two of the schools reporting incidents are in the Georgetown neighborhood: Hardy Middle School and Duke Ellington School. The latter is located on R Street, a few blocks from the Georgetown campus.

The FBI is working to identify the substance and is taking down the names of people who were exposed. No one who was in contact with the material has showed signs of illness, and no students were in danger at any point.

The FBI could not be reached for comment.