Facebook site evacuated after mail tests positive for sarin

A Facebook mail processing warehouse near company hequarters at California, United States was evacuated on Monday as officials are working to determine what caused mail to test positive for nerve nt sarin.

Menlo Park Fire Marshal Jon Johnston said Monday that incoming mail undergoing routine processing by machine tested positive for sarin, but that re are reports of injuries at Silicon Valley site.

"Right w we don't have anybody that has any symptoms," he said. "We're just doing verification", he ded. 

FBI is assisting in investigation, as is common in incidents such as this one.

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Facebook spokesman Anthony Harrison said four buildings were evacuated and that three buildings have been cleared for people to come back in.  suspicious pack was delivered around 11 am to one of company's mail rooms, he said.

"Authorities have t yet identified substance found," Harrison wrote.

Federal Centers for Disease Control and Prevention says sarin is a chemical warfare nt that is a clear, colorless, odorless and tasteless liquid. It can evaporate into environment, prompting symptoms within seconds.

A drop of sarin on skin can cause sweating and muscle twitching, and exposure to large doses can result in paralysis and respiratory failure leing to death. CDC says people who are mildly exposed usually recover completely.

In 1995, members of a doomsday cult unleashed a dely sarin attack in Tokyo subway system, killing 13 people and sickening more than 6,000. cult leer, Shoko Asahara, and several followers were executed in 2018 for ir roles in crime.

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in December 2018, Facebook evacuated its hequarters after receiving an anymous bomb threat that turned out to be a false alarm.

Facebook is updating its terms and services guidelines to clarify how it makes money from personal information of its users.