The troubled part-privatisation of the probation service has taken another hit with one new owner, Working Links, planning hundreds of redundancies across the country.

The group, which is a public, private and voluntary-sector company whose shareholders include Capgemini, Manpower and the Department for Work & Pensions, is understood to be planning 200 job cuts in the Welsh probation service alone.

This has prompted Leanne Wood, the leader of Plaid Cymru who is a former probation worker, to write to Carwyn Jones, the First Minister of Wales, demanding he “use whatever powers you have to mitigate job losses”. The letter, seen by The Independent, added that Miss Wood has “grave professional concerns about our capacity in Wales to give offenders the care, attention, and time they require”.

The reforms were overseen by the former Lord Chancellor Chris Grayling. He privatised 70 per cent of the service in England and Wales, with only the most dangerous offenders still looked after by the state.

Mr Grayling confirmed last December that the private sector would be handed 21 “Community Rehabilitation Companies” (CRCs) in deals that are worth around £450m a year.

Aside from Wales, Working Links runs the Bristol, Gloucestershire, Somerset and Wiltshire CRC and another that covers Dorset, Devon and Cornwall – further job cuts are expected in both.

One CRC, the Sodexo-run South Yorkshire region, has failed a Ministry of Justice audit and has until February to improve or be renationalised.

Napo, the probation union, has long claimed that privatisation would cause redundancies and a poorer service, but ministers believe that greater commercial nous will reduce the costs of Britain’s highly expensive legal system.

Ministry sources confirmed that an audit of the Kent, Surrey and Sussex CRC, run by Seetec Group, had “identified some areas for improvement”. But the situation is not as bad as that in South Yorkshire, where the MoJ audit found “lack of contact with offenders, ineffective enforcement and little or no evidence of any offence- or risk-focused work”.

A Napo spokeswoman said: “Napo said from the outset that privatising the probation service would have a negative impact on the quality of service our members provide as profit becomes a priority over public protection and quality. We are now seeing our fears become a reality and urge the Government to urgently review all the CRCs’ performance.”

A Working Links spokesman said: “After careful consideration, we are starting to streamline our support services across the business and have opened up opportunities for voluntary redundancy for those wishing to leave our CRCs.

“This will be an enhanced package and it is our aim, wherever possible, to avoid compulsory redundancies.

“We are consulting with the unions and our people on our proposed new way of working across the organisation. At this stage we are simply looking for expressions of interest of those people who may wish to leave the organisation.

“Our front line delivery will not be negatively impacted by our proposed changes.”