The most comprehensive examination of the UK's asylum system ever conducted has found it "marred by inhumanity" and "not yet fit for purpose".

The report, published by the Independent Asylum Commission, is a damning indictment of the Home Office's failure to deal fairly with those applying for sanctuary in this country.

The commission found that Britain's treatment of asylum-seekers "falls seriously below the standards to be expected of a humane and civilised society". Its interim report will be delivered to the Home Office today by a delegation of asylum-seekers.

Download the new Independent Premium app Sharing the full story, not just the headlines

The report details how the "adversarial" system is failing applicants from the very first point of interview, with officials accused of stacking the odds against genuine claimants. "A 'culture of disbelief' persists among decision-makers," it said. "Along with lack of access to legal advice for applicants this is leading to perverse and unjust decisions."

The findings are the result of the most thorough look at the system in history, with testimonies from every sphere of society, including three former home secretaries, more than 100 NGOs, 90 asylum-seekers, the police, local authorities, and hundreds of citizens.

All-day hearings were held in seven major cities, where hundreds of people gave evidence, from those who brand the system too lenient to those who think it is a blot on the country's human rights record.

As well as this current information, an independent academic body was tasked to gather all documents already published on the issue in the past five years, from both sides of the political spectrum.

Three areas of the system came under particular fire. The use of detention centres – especially to lock up children, pregnant women and torture victims – was condemned, as was the often brutal handling of removals, and the use of destitution as a tool to drive claimants out of the country.

Sir John Waite, co-chair of the commission said: "The overuse of detention, the scale of destitution and the severity of removals are all areas which need attention before the system can be described as fit for purpose".

The commissioners found that locking up those seeking asylum was costly and often completely needless. "The detention of asylum-seekers is overused, oppressive and an unnecessary burden on the taxpayer," they said. The detention of children was in turn branded "wholly unjustified".

Daily coronavirus briefing No hype, just the advice and analysis you need Enter your email address Continue Continue Please enter an email address Email address is invalid Fill out this field Email address is invalid Email already exists. Log in to update your newsletter preferences Register with your social account or click here to log in I would like to receive morning headlines Monday - Friday plus breaking news alerts by email Update newsletter preferences

Sir John called for "a thorough re-examination" of the detention and bail system, which he said treated asylum-seekers like criminals. "The justification for such a system is the fear of absconding, and that fear is, in our opinion, grossly exaggerated," he said.

According to the commission, factors such as post-traumatic stress were not considered enough when asylum-seekers had their initial interviews with border officials. Victims of rape and torture who might initially find it difficult to describe their experiences sometimes had their cases overlooked because they only described these incidents in later conversations.

"Some of those seeking sanctuary, particularly women, children and torture survivors, have additional vulnerabilities that are not being appropriately addressed," it found.

Cuts in the legal aid budget have also made it more difficult for those with complex cases to find lawyers to take them on, resulting in many genuine claims being overlooked. Removals by private security firms were described by the commission as being carried out with "unnecessary violence and carelessness". The commission said it had heard testimony of the "very severe handling" of claimants, and criticised the absence of any monitoring system to follow-up on the fate of those removed.

The Liberal Democrats' home affairs spokesman, Chris Huhne, said: "The whole system is fundamentally a mess and broken, and this report makes a pretty good job of summarising that. The asylum system combines incredible complexity with systematic incompetence, and thousands wait for a decision year after year".

Donna Covey, chief executive of the Refugee Council, said: "This is an important set of findings from an independent commission, which presents overwhelming evidence that the asylum system is still not fit for purpose.

"It is surely now time for the Government to take a long hard look at the way it treats people seeking sanctuary on our shores. We must treat people with basic decency, and the system must get asylum decisions right – they are a matter of life and death."

While the report disclosed the initial findings of the commission, further publications in May, June and July will also include recommendations on how to deliver reform and rectify problems in the system.

Yeukai Taruvinga, 25: 'I found the treatment very brutal. I was expecting to receive sanctuary'

Yeukai Taruvinga, has seen first hand the iniquities of the asylum system. A student activist from Zimbabwe, she fled to the UK in 2001, after persecution for her support of the opposition party Movement for Democratic Change (MDC).

When she arrived in Britain she thought things would improve, but life was not as she'd hoped. "I was expecting to receive sanctuary, but when I came to the UK it was a completely different scenario. I found the treatment of asylum-seekers was very brutal and inhumane".

"I was detained several times without committing any crime – just because I was an asylum-seeker," she said. "My treatment by officers was very rough, and in one centre I was put into a cell with no windows and a dirty bed. If you needed help there was no way of calling because the reception was so far away. All we could do was bang on the door."

She has been transported around the country between three different detention centres, never knowing if they were sending her home or moving her on. "It was very traumatic and they never explained why they were moving me", she said. "I kept thinking they were about to take me back to Zimbabwe".

Ms Taruvinga has not been in detention now since 2005, but when she was first released she was left with nowhere to go and nothing to eat. After being told she was not entitled to any support, she was forced to beg from churches to find food to eat.