The Home Office offered bonuses to the private firm responsible for removing Windrush citizens, on exceeding its deportation targets, newly released documents show.

Letters from the Home Office to a parliamentary committee also reveal the department may be withholding crucial evidence about wrongful detentions and removals from an inquiry into the scandal.

Figures released by the home secretary after a request by the Joint Committee on Human Rights show the department’s contract with outsourcing company Capita gave the company a bonus payment of 2.5 per cent, above a certain target for removals from the UK. This increased to 12.5 per cent if the total exceeded the target by 10 per cent.

Harriet Harman, chair of the committee, wrote to Sajid Javid last month seeking details of the contract with Capita, which was contracted to deal with people who applied for leave to remain in the UK but had been refused – a position many of the Windrush citizens found themselves in.

The home secretary responded that Capita operated an “outcome-based payment mechanism” between 2012 and 2016, with no individual bonuses for staff. There were, however, overall incentives to beat removal targets, he added.

After the firm waived concerns about commercial sensitivity, the Home Office sent the committee the section of the contract detailing the incentive scheme, which showed the it was paid between £10.58 and £22.63 per person contacted who left the UK voluntarily.

A Capita spokesperson said the firm's role was to contact the list of individuals provided by the Home Office, and claimed it did not receive any incentive payments under Clause 1.5 of the contract.

Separate documents released by Mr Javid to the Committee also reveal that the department is producing only “case summaries” for the individuals identified to be shared with the independent reviewer, Wendy Williams, for further examination.

Ms Harman said it was “crucial” that the case files of Windrush citizens caught up in the scandal were revealed in full. In a letter to the home secretary, she cited the cases of Anthony Bryan and Paulette Wilson, whose files were released on the Committee’s request in June and revealed multiple failings by the Home Office.

“The Home Office failed to take account of evidence that was on their files on multiple occasions and detained them without adequate justification,” she wrote.

Earlier this month, Home Office figures revealed more than 160 Windrush citizens could have been wrongfully detained or deported from the UK.

Responding to the revelations on Capita’s incentivised contract, shadow home secretary Diane Abbott, said: “It is truly shocking that Home Office contracts explicitly incentivised Capita to profit from Theresa May’s deport-first, ask-questions-later approach.

“The true scale of this scandal is still being revealed and the Home Office have not come clean about how many of our fellow citizens were deported, forced into so-called voluntary deportations or detained as prisoners in their own country.

“Time and again under the Tories, private profit is put ahead of the public interest and even the rights of British citizens.”

Windrush generation: threat of deportation from UK Show all 15 1 /15 Windrush generation: threat of deportation from UK Windrush generation: threat of deportation from UK The ex-troopship 'Empire Windrush' arriving at Tilbury Docks from Jamaica, with 482 Jamaicans on board, emigrating to Britain. Getty Windrush generation: threat of deportation from UK Jamaican immigrants being welcomed by RAF officials from the Colonial Office after the ex-troopship 'Empire Windrush' landed them at Tilbury. PA Windrush generation: threat of deportation from UK Alford Gardner who arrived in Britain in 1948 on the first Windrush ship to dock in Tilbury, Essex, speaking at his home in Leeds PA Windrush generation: threat of deportation from UK Alford Gardner in Leeds shortly after he arrived in Britain in 1948 on the first Windrush ship to dock in Tilbury, Essex PA Windrush generation: threat of deportation from UK Gardner was 22 years old when he boarded the ship in Kingston, Jamaica, with his brother Gladstone before they and hundreds of Caribbean migrants called on to rebuild post-war Britain disembarked the ship in Tilbury Docks PA Windrush generation: threat of deportation from UK Alford Gardner (right), during his RAF service in 1947 PA Windrush generation: threat of deportation from UK The son of Ruth Williams, a Windrush-generation immigrant, wants to the leave the country after threats of deportation. According to his mother, Mr Haynes applied for British citizenship in 2016 but was rejected, despite Ms Williams having lived in the UK almost permanently since arriving from St Vincent and the Grenadines in 1959. Ruth Williams, 75, said she felt "betrayed" by Britain after the Home Office twice turned down applications for her 35-year-old son, Mozi Haynes, to remain in the country. Ms Williams is understood to have cancer and said she relies heavily on her son for support. PA Windrush generation: threat of deportation from UK The British liner 'Empire Windrush' at port in 1954. Getty Windrush generation: threat of deportation from UK Ruth Williams, 75, with her British passport. "I feel betrayed and a second class citizen in my own country," she said. "This makes me so sad and the Home Office must show some compassion. "I am unwell and almost 75, I live on my own and I need my son to stay here. I need my family around me and I can’t face being alone. He has applied to the Home Office and been refused twice." PA Windrush generation: threat of deportation from UK From the top, hopeful Jamaican boxers Charles Smith, Ten Ansel, Essi Reid, John Hazel, Boy Solas and manager Mortimer Martin arrive at Tilbury on the Empire Windrush in the hope of finding work in Britain. Getty Windrush generation: threat of deportation from UK Jamaicans reading a newspaper whilst on board the ex-troopship 'Empire Windrush' bound for Tilbury docks in Essex. Getty Windrush generation: threat of deportation from UK After half a century in Britain, Anthony Bryan decided it was time to go abroad. But the decision set off a nightmare that saw him lose his job, detained twice and almost deported to Jamaica. AFP/Getty Windrush generation: threat of deportation from UK Jamaica-born Anthony Bryan poses outside his home in Edmonton, north London. Now 60 and a grandfather, Bryan thought the issue could be resolved swiftly, as he legally moved to Britain with his family as part of the Windrush generation of Caribbean migrants after World War II. In 1948, the ship Windrush brought the first group of migrants from the West Indies to help rebuild post-war Britain, and many others followed from around the Commonwealth. A 1971 law gave them indefinite leave to remain, but many never formalised their status, often because they were children who came over on their parents' passports and then never applied for their own. AFP/Getty Windrush generation: threat of deportation from UK Three Jamaican immigrants (left to right) John Hazel, a 21-year-old boxer, Harold Wilmot, 32, and John Richards, a 22-year-old carpenter, arriving at Tilbury on board the ex-troopship 'Empire Windrush', smartly dressed in zoot suits and trilby hats. Getty Windrush generation: threat of deportation from UK Newly arrived Jamaican immigrants on board the 'Empire Windrush' at Tilbury in 1948. Getty

A Capita spokesperson said: “In relation to the contact management and casework services contract, Capita’s role was to contact the list of individuals provided by the Home Office.

"Capita’s focus was on achieving quality targets and we did not receive any incentive payments under Clause 1.5 of the contract. The contract ended in October 2016.”