A Facebook spokesman says a package that initially tested positive for sarin at a mail facility near the company’s headquarters in California did not contain any dangerous substance.

“Authorities have confirmed test results were negative for any potentially dangerous substance and the buildings have been cleared for re-population,” spokesman Anthony Harrison said in a statement Tuesday to the San Jose Mercury News .

Authorities put the site under quarantine Monday. Four buildings were evacuated. The suspicious package was delivered around 11 a.m. to one of the company’s mail rooms, Harrison said.

Workers who handled the package did not report any ill effects.

There were no reports of injuries, Menlo Park Fire Marshal Jon Johnston said. Incoming mail undergoing routine processing by machine tested positive for sarin, he said.

(AP)