UNITED Nations officials have arrived in Scotland to investigate allegations that Westminster welfare reforms have led to “grave or systematic violations” of disabled people’s human rights.

The Sunday Herald revealed in August that the Special Rapporteur and members of UN’s Committee on the Rights of Persons with Disabilities (UNCRPD) were due to visit the UK to probe the complaints and take evidence from individuals and campaign groups, including in Scotland.

Officials arrived this weekend and will spend around two weeks visiting all four of the UK's nations. All investigations are being conducted in private with participants being asked to sign confidentiality agreements.

The UN investigators will specifically examine whether the British government has committed "systematic and grave violations" of the Convention on the Rights of Persons with Disabilities. The UK is the first country in the world to be investigated in this manner.

Meanwhile the Scottish disability campaign group Black Triangle has also revealed it plans to take another complaint to the UN Special Rapporteur under protocols which allow individuals to lodge cases where there is believed to be a “life-threatening situation” or urgent action is required.

Black Triangle said their complaint will focus on the case of Michael O’Sullivan, a disabled father-of-two with severe mental health issues, who killed himself after he lost access to his disability benefits.

Last month, in what is believed to be the first case of its kind, a coroner directly attributed his suicide to being found “fit for work” following an assessment under the controversial work capability process.

John McArdle, co-founder of Black Triangle, said he could not make any comment on the current UN investigation. However, he said the group were planning to submit a separate complaint to the Special Rapporteur which would focus on O’Sullivan’s case.

Black Triangle has also compiled a dossier of more than 80 deaths linked to welfare reform, including a 44-year-old man with mental health conditions whose benefits were cut after he was deemed fit for work.

He was left with £40 a week to live on and was badly malnourished when he died, weighing just 5st 8lbs.

The group, which was set up to campaign against benefits cuts, is named after the black triangle which the Nazis forced people with disabilities to wear in concentration camps to show they were 'workshy'.

Last month the Sunday Herald revealed how the UN investigation was triggered by a complaint submitted by Black Triangle’s sister campaign group Disabled People Against Cuts (DPAC), which contained more than 40 issues cited as evidence that “attacks are being carried out in every area” of disabled people’s lives by the UK Government.

The issues outlined include the impact of the bedroom tax, problems which have been caused by changes to disability benefits and an overall one per cent cap on annual benefit rises. It also raised concerns about the impact of benefit sanctions and workfare programmes, as well as inaccessible public transport and cuts to mobility allowances.

A DPAC spokeswoman said: "Many disabled people are facing a multitude of attacks on their human rights and living standards.

"It is rarely just one or two issues per person. This is the crucial point in the current retrogression of the human rights of disabled people."

Last night a spokesman for the Department of Work and Pensions said: "We are committed to supporting the most vulnerable people in society and spend more than £50 billion every year on disabled people and their services. We are happy to inform the inquiry of this."