A Facebook employee has died at the company's headquarters campus in Silicon Valley in what police call an apparent suicide.

Horrified bystanders in Menlo Park, California called 911 at about 11.30am on Thursday after an adult male jumped from the top of a four-story building on the 100 block of Jefferson Drive.

Paramedics rushed to Facebook's sprawling campus and rendered first aid, but the victim was declared dead on the scene.

The deceased individual has not been publicly identified pending family notification, but Facebook confirmed in a statement to DailyMail.com that he was an employee.

A Facebook employee jumped to his death from the building seen center-left at the company's Silicon Valley headquarters on Thursday

'We were saddened to learn that one of our employees passed away at our Menlo Park headquarters earlier today,' the statement said.

'We're cooperating with police in their investigation and providing support to employees. While the family is being notified, we have not information to share,' the statement continued.

'We hope to provide an update when we learn additional information from law enforcement.'

Police say that the initial investigation indicated that there is no foul play involved in the death.

The entrance to the Facebook campus is seen in a file photo. The company says it is cooperating with law enforcement and offering support to employees

The San Mateo County Coroner's Office will determine the official cause and manner of death.

Facebook has approximately 39,651 full-time employees around the world, with several thousand working at the Menlo Park headquarters.

If you or someone you know is having a crisis, please call the National Suicide Prevention Lifeline at 800-273-8255, or text the Crisis Text Line at 741-741.