A high school in California has converted a girls' restroom into a gender-neutral facility to accommodate transgenders as well as male and female students.

However, the move taken on Friday by the Santee Education Complex in Los Angeles sparked protest from concerned parents in the community. They rallied on Tuesday outside the gates of the high school, which is under the second largest school district in the U.S.

School administrators opened the facility on Friday after receiving a petition from the school's Gay Straight Alliance. The petition was signed by 700 students and staff. Members of the alliance also picketed the school after a transgender male was prevented by a janitor from using the girls' restroom, the Christian News Network reports.

"I feel empowered. I feel like I can do anything. I feel like my voice was heard," one student told Fox 11 Los Angeles after the facility was opened.

However, some students have expressed concern about their safety, but the alliance says a "text tip" programme is enough along with monitoring by school staff and alliance members.

"Our bathrooms will be monitored. We have a text a tip program so we can text a tip for any concerns or anything, like if anything happens. So, it will be completely safe," student Juliet Dominguez said.

During Tuesday's protest outside the school gate, a fight broke out when Santee students confronted the protesters, KABC reports. The police said some students threw objects at the protesters.

"Our students who advocated for the gender-neutral restrooms are the real heroes since this valuable experience allowed them to develop leadership skills that will prepare them for college and career," Santee Principal Martin Gomez said, according to Reuters.

Other neighbouring districts have a single stall all-gender restrooms and Santee is the first to have such a facility.

Meanwhile, the University of Toronto temporarily revoked a gender-neutral restroom after two incidents of voyeurism were reported.