OTTAWA — The federal prison ombudsman says there's an "immediate and troubling" shortfall in mental health-care services for offenders -- a problem that will only grow as more people are locked away.

In his annual report released Monday, Correctional Investigator Howard Sapers says there are still gaps in capacity, quality and standards when it comes to helping mentally ill prisoners.

"Criminalizing and then warehousing the mentally ill burdens our justice system and does nothing to improve public safety," Sapers wrote in the highly critical report.

The gap between the number of aboriginal and non-aboriginal offenders is widening, and there are still many major roadblocks to helping women prisoners, the correctional investigator found.

Ten to 12 per cent of offenders entering the federal prison system have a significant mental problem.

Sapers said in an interview he expects the prison population to increase by about 10 per cent -- or as many as 1,300 people -- in coming years due to legislative changes to toughen sentencing and limit early release.

"We're going to see this manifested in some troubling ways."

The prison service already has only about 50 per cent of the acute psychiatric care beds it requires, said Sapers.

"So any increase in the number of offenders incarcerated will lead to an increased demand in that area. It will require new resources, and it will require a continued commitment from the service."

Incidents in which prisoners harm themselves -- from slashing arms with sharp objects to attempting suicide -- are on the rise, says the report.

Sapers calls for the hiring of more mental health professionals and additional care units to deal with such offenders in each region. He also recommends management plans be drafted for the most serious mental health cases.

"The system will have to build capacity, but capacity doesn't expand overnight," Sapers said. So as incarceration levels rise, "it's going to be all that more difficult for the service to respond."

In a written response to his report, the Correctional Service outlined the steps being taken to address the issues, but notes more money is needed.

Sapers has repeatedly called for significant action to improve the care of mentally ill prisoners.

In September he said the risk that more mentally ill inmates will needlessly die behind bars was still unacceptably high.

He said the prison system's response to at least 17 in-custody suicides in the last two years has been lacking. Sapers slammed the prison service over the death of 19-year-old Ashley Smith, who choked herself with a strip of cloth at the Grand Valley prison in Kitchener, Ont.

Following a meeting last week in Fredericton, federal, provincial and territorial ministers for justice and public safety acknowledged the problems related to mental health and the justice system.

They agreed the issue would be a standing agenda item for future meetings, and called on officials to begin discussions when they next meet in January.

Sapers said he was pleased by the communique, adding that federal Public Safety Minister Peter Van Loan "has been true to his word" on championing the mental health agenda.

"In the meantime, we still have a Correctional Service that does not have adequate capacity. The need for mental health intervention is not being met."

Sapers' report says the aboriginal rate of imprisonment is nine times the national average, and that one in five offenders is of aboriginal ancestry. One-third of the female prison population is aboriginal.

Dedicated and focused leadership within the prison service is needed to deal with the issue of over-representation of natives in the system, he said.

He also chastised the service for refusing to give the deputy commissioner for women full and direct authority for all matters affecting female prisoners.