The father of the woman identified as the YouTube HQ shooter said he had warned police she might be headed to the video-sharing site's offices because she "hated" the company.

Nasim Aghdam, 39, of Southern California, was identified by US media as the woman who approached the Silicon Valley campus around lunchtime on Tuesday and began to fire before entering the building of the Google-owned video sharing service.

One man and two women were shot in the incident before the female shooter apparently committed suicide.

Hospital officials have said the 36-year-old man is in critical condition and two women, aged 32 and 27, are in a serious and fair condition. A fourth person hurt suffered a sprained or broken ankle.

Aghdam was angry at YouTube because it had stopped paying her for videos she posted on the platform, her father told the Bay Area News Group .