Asylum seekers detained by the Home Office and threatened with deportation to Rwanda are set to take legal action against the government after Rishi Sunak admitted that no flights will take place before the general election. The Home Office started raiding accommodation and detaining people who arrived at routine immigration-reporting appointments on 29 April in a nationwide push codenamed Operation Vector. Some have been held in immigration removal centres for a month, despite the prime minister announcing that flights would not start until after the 4 July election – and only “if I’m re-elected as prime minister” – while Labour has vowed to scrap the scheme if it wins the election. The Observer can reveal that as recently as Tuesday, the Home Office’s lawyers were fighting legal challenges from detained asylum seekers on the basis that flights to Rwanda were “imminent” and “progressing”, despite the government legal department telling the high court on the same day that there would be no flights before the election. Laura Smith, co-head of legal at the Joint Council for the Welfare of Immigrants, said she was personally involved in a case where the Home Office “insisted on maintaining detention” after Sunak’s statement. “I do think there will be valid claims for damages,” she added. “In our experience, Home Office lawyers are still acting as though nothing has changed. There seems to be utter confusion, causing immense distress to our clients.” Lawyers representing detained asylum seekers told the Observer they were mounting challenges for unlawful detention, even before the prime minister’s statement, because people were being seized without the Home Office making the legal decisions necessary to send them to Rwanda. Lewis Kett, a solicitor at Duncan Lewis, said: “There was no justification for detaining them nine to 11 weeks before any potential flights, and even less so after the prime minister announced no flights would leave before the election. “There are questions as to whether he knew this would be the case when the detention operation began. They are almost all likely to have strong claims for unlawful detention and compensation.” The Home Office has refused to disclose how many asylum seekers have so far been released on immigration bail and how many remain detained. The charity Detention Action warned that several people it was supporting were suffering from depression, anxiety and suicidal thoughts while being held for Rwanda flights. Its deputy director, Jade Glenister, said: “With many people held in detention since the end of April, it is clear that their removal was never ‘imminent’. Their detention was never justified. They should be urgently released into safe and supportive accommodation.” The fresh legal cases come on top of three other challenges to be heard at the high court this week. A preliminary hearing for a case against the new “safety of Rwanda” guidance for civil servants, brought by the charity Asylum Aid, will be heard on Monday alongside a challenge by an asylum seeker selected for Rwanda. Thursday will see the high court consider arguments by the FDA civil service union that the safety of Rwanda bill is unlawful because it allows ministers to order civil servants to ignore European court of human rights injunctions. Home Office sources say civil servants have been told to continue implementing the Rwanda plan and the Tories’ new small boat laws, despite Labour pledging to scrap both. “There are Home Office staff currently being onboarded and relocating to Rwanda in the last week of June,” one official told the Observer. “Implementation has not stopped – we are still squandering money on those gimmicks. It’s all a waste of time and money on the off chance that the Tories win the election.” One job advert for a Kigali-based “first secretary” for the programme did not close until Monday, four days after Sunak’s statement. It said the role required a person with a “strong grip on big and contentious issues” and “sound political judgment”. The document said a “small Home Office team” would be based in the Rwandan capital to “drive forward the delivery” of the partnership and “make high-risk decisions”. Meanwhile the Conservatives’ flagship Illegal Migration Act, which Sunak pledged would enable the government to detain and remove small boat migrants, has not yet been implemented. With the election coming almost a year after it received royal assent, civil servants believe it will never be brought into force. “We are still working as usual, although everyone wonders why,” the official said. A report released by parliament’s public accounts committee on Wednesday said 50,000 asylum seekers are now “in limbo” because the government refuses to consider their claims but has no way of deporting them.