An anthrax scare shut down Florida’s highway safety agency Monday morning, including 1,100 state workers who were subsequently sent home.

According to the Miami Herald, the threat was identified as a letter containing a white powder that read, “This is anthrax and I hope u die,” said Julie Jones, the highway safety director and the addressee of the letter.

Officials said a hazardous materials team has studied the letter and put up yellow crime scene tape but has not found any anthrax.

“What a mess,” Jones said. “We believe that everybody was safely evacuated out of the building.”

Lt. Mike Bellamy of the Tallahassee Fire Department said seven state workers were still inside the building on the second-floor records unit where the letter was discovered in order to preserve the crime scene, though they were visited by a team with special respiratory equipment.

According to the Centers for Disease Control and Prevention, humans can become infected with anthrax by handling products from infected animals including wool, for example, or by eating undercooked meat from infected animals.

In most cases, early treatment with antibiotics can cure cutaneous anthrax, with 80 percent of of those who do not receive treatment surviving.

Gastrointestinal anthrax, however, is considered more serious, with between 25 percent and 50 percent of cases resulting in death.

The most severe form of anthrax is that which is inhaled. In 2001, when anthrax was dispersed through the U.S. postal system, about half of the cases resulted in death.

Symptoms for cutaneous anthrax include a small sore that develops into a blister, which then turns into a skin ulcer with a black area in the center.

Gastrointestinal anthrax causes nausea, loss of appetite, bloody diarrhea and fever, followed by severe stomach pain.

Finally, in the case of inhalation, symptoms are similar to that of a cold or flu and include a sore throat, mild fever and muscle aches that develop into a cough, chest discomfort and a shortness of breath.