Mental health nurses are to be posted in Sussex police stations and courts in a bid to reduce reoffending by mentally ill criminals.

The £25 million pilot scheme, which is to be tested in 10 areas across England, including Sussex, will mean people with mental health problems are treated “as early as possible”, care and support minister Norman Lamb said.

It comes after a successful pilot of mental health nurses going out to incidents with police on the beat in Eastbourne.

The project between Sussex Police and Sussex Partnership NHS Foundation Trust’s scheme to help improve services for people facing mental health crises in Eastbourne has already been used more than 80 times in its first nine weeks.

Since it began in October last year there has been a reduction in the number of people detained for assessment under Section 136 of the Mental Health Act.

This new scheme, launched on Saturday, will see nurses at police stations and courts.

Identifying people with mental health needs who come into contact with the criminal justice system at the earliest possible stage will help to “divert” them away from offending again, Mr Lamb said.

He said “too often” criminals with mental health problems, learning difficulties or substance misuse issues are only diagnosed once they reach prison.

The majority of people who end up in prison have mental health problems, a substance misuse problems or learning disabilities, and one in four has a severe mental health illness such as depression or psychosis, a Department of Health spokeswoman said.

Over the next year the money will be used to join up police and courts systems with mental health services in Sussex and nine other counties.

Mentally ill people as well as those with substance abuse problems and learning disabilities will be assessed when they come into contact with police.

The information will be shared with officers and the courts system to ensure charging and sentencing decisions take into consideration a person’s health needs, the spokeswoman said. It will also mean treatment is given sooner, which will help stop reoffending, she added.

If the pilot is successful the measure will be rolled out across the rest of the country by 2017.