Reports of abuse inside residential facilities and hospitals for the disabled and mentally ill surged 37 per cent to 287 last financial year, up from 209 the previous year. But there are fears these cases represent the "tip of the iceberg" because many residents, patients and staff are incapable of reporting such incidents or too frightened to do so.

The 287 cases, reported by "Community Visitors" who inspect facilities for the Public Advocate, include a frail, non-verbal elderly person having their leg and knee cap broken in two separate attacks by a staff member in a group home, and a mentally ill man being punched in the head by a nurse at a hospital because he was suspected of smoking in his room.

The report also highlighted concerns about restraint tactics used on mentally ill patients causing injuries and sexual assaults occurring when mentally ill women and men are housed together in psychiatric units. In one case, a female patient was placed in the male section of a unit despite reporting she had been sexually assaulted there on a previous admission.

While $6 million has been allocated under the government's "Safety of Women in Mental Health Care" plan to create more female-only areas in psychiatric services, the Women's Mental Health Network Victoria said more needed to be done to ensure these spaces were secure, and to increase the number of them.

Public Advocate Colleen Pearce said she was concerned a shortage of services and staff for disabled and mentally ill people was fuelling abuse. She said while most most incidents of violence and abuse were managed well, some were not. For example, staff who reluctantly reported the two serious attacks on the frail, non-verbal elderly patient for fear of retribution were disciplined by the Department of Human Services for not speaking up sooner.

"It was particularly disappointing to me that when these individuals were finally convinced to report their concerns to DHS management that disciplinary action against these 'whistleblowers' was proposed over their delay in reporting the abuse," she said.

The staff member responsible for the attacks was later charged with criminal offences.

In a separate case, the report said, staff at another home delayed reporting that a worker had kicked, choked and pinned down a resident in front of other staff, because they were intimidated by the perpetrator.

Ms Pearce and volunteer community visitors called for an inquiry into group homes and full public reporting of all incidents and allegations of abuse and neglect.

"Abuse and neglect of people with disability is completely intolerable, and even more so when it is committed, overlooked or ignored by those entrusted with their care," Ms Pearce said.

Minister for Mental Health and Community Services Mary Wooldridge did not respond to calls for an inquiry last night, but said the government was working hard to encourage a "zero tolerance" approach towards abuse which meant staff must report cases.

Opposition community services spokeswoman Jenny Mikakos said the Minister had not done enough to stop the "disturbing" trend. But she did not commit to an inquiry, saying she had to first sit down with the Public Advocate to discuss the report.