Two people possibly exposed to Sarin nerve agent at Facebook mailing facility

Two people may have been exposed to Sarin at a Facebook mailing facility, fire officials say.

The incident happened at a mail handling center owned by Facebook in Menlo Park, California on Monday.

San Mateo County Fire Officials told ABC that everyone is safe and two people are being checked out.

Authorities say they were alerted to the substance while testing a package for hazardous chemicals.

Sarin is a clear, colorless liquid that is an incredibly toxic nerve agent. It can evaporate and turn into a gas, allowing it to easily disperse.

A second open air test at the facility came back negative.

Hazmat crews have been deployed to conducte another test.