The 22-year-old was one of four New York-based students who launched Diaspora as a "privacy-aware, user-controlled" social network.

It was set up in response to criticism that Facebook was not handling the privacy of its users well.

The cause of Mr Zhitomirskiy's death is yet to be determined. The San Francisco coroner's office said it will have details in several weeks time.

Read more: http://www.bbc.co.uk/news/technology-15736807