Facebook buildings in San Francisco, Calif., were evacuated Monday after a suspicious package tested positive for sarin in the Facebook mailing facility.
All mail sent to the facility is pre-screened by machines to detect hazardous substances and employees were alerted before the package was handled internally, according to NBC San Francisco. Four buildings were initially evacuated, but three have since been deemed safe and resumed operations. Initial reports from firefighter officials said that two employees may have been exposed, but they have since corrected the record to say that no employees having been exposed at this time.
Facebook says the substance has yet to be officially determined by officials and that the screening device can only say what the substance might be.
“At 11:00 AM PDT this morning, a package delivered to one of our mail rooms was deemed suspicious,” a Facebook spokesperson said. “We evacuated four buildings and are conducting a thorough investigation in coordination with local authorities. Authorities have not yet identified the substance found. As of now, three of the evacuated buildings have been cleared for repopulation. The safety of our employees is our top priority and we will share additional information when it is available.”
Sarin gas, as defined by the Centers for Disease Control and Prevention, is a nerve agent often used as a chemical weapon noted for its lethality, toxicity, and ability to be rapidly deployed. The colorless, odorless liquid that evaporates into the air and spreads through whatever environment it is placed in was developed in the 1930s by Germany and was used in two terrorist attacks in the 1990s in Japan.
A senior White House official confirmed in April 2017 that the Bashar Assad regime in Syria used sarin gas in a chemical attack against its own citizens. The Syrian government has been accused of using sarin gas attacks multiple times on its own citizens during the course of the country’s civil war that started in 2011.
People with “mild” exposure often recover completely, but the CDC notes that those more “severely” exposed have a lower chance of survival.
UPDATE: A second test later proved negative for sarin, and Menlo Park Fire Chief Harold Schapelhouman told the Los Angeles Times that no one had been exposed to sarin and an open-air test had also come back negative.
