The FBI alerted about 500 scientists at the University of Washington about suspicious mail after COVID-19 scientists on the East Coast received a mysterious package, according to Buzzfeed News. “The mail did contain an unknown substance that has not yet been identified as a hazardous substance, however, confirmatory testing to identify the substance is not yet complete,” the email read. The FBI declined to elaborate on the particular incident, leaving out which researchers received the suspicious mail, what was exactly in it, or any potential motives that the sender may have had.