Photo: JOSH EDELSON/AFP/Getty

Silicon Valley Facebook employees evacuated after a package sent to one of the company’s mail facilities tested positive for a poisonous chemical agent on Monday.
Four buildings in Menlo Park, where the company is headquartered in Northern California, were emptied after a package was “deemed suspicious,” Facebook spokesperson Anthony Harrison told PEOPLE in a statement.
“At 11:00 AM PDT this morning, a package delivered to one of our mailrooms was deemed suspicious,” Harrison said.
Johnston said that there were no injuries to report so far.
“Right now we don’t have anybody that has any symptoms,” he told the AP. “We’re just doing verification.”
There is a possibility that the test could be a false positive, localABC7 journalist Chris Nguyen reported on Twitteron Monday.
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Sarin is a man-made chemical nerve agent, which is the “most toxic and rapidly acting of the known chemical warfare agents,” according to theCenter for Disease Control and Prevention‘s website.
Symptoms of exposure to the chemical — which was originally created in Germany as a pesticide — vary in severity, ranging from runny nose and watery eyes to diarrhea, nausea, vomiting, headache and changes in heart rate or blood pressure.
People who are mildly exposed to the agent usually recover quickly, according to the AP’s report.
source: people.com