Thousands of people marched through London today, accompanying bereaved families whose loved ones have died in Police custody and are demanding an urgent meeting with the Prime Minister and London Mayor.

The relatives of Chris Kaba, Oladeji Omishore, Matthew Leahy, Jack Susianta and Leon Patterson – who all died in prison, police custody or mental health settings – signed a letter addressed to Rishi Sunak which they personally delivered to Number 10.

The families are calling for major changes to the judicial process following the state-related deaths and have said the government is failing Britons.

Protesters joining them on the march from Trafalgar Square chanted ‘police are the murderers’ and held signs reading ‘end Taser deaths now’ and ‘failed by the state’ as they gathered on Parliament Street in central London.

Bridgerton actress Adjoa Andoh also spoke at the march, and read out the names of all the people who have died since 1970 – a list she said is just getting ‘longer and longer’.

In an emotional speech outside Downing Street, Helen Nkama, the mother of 24-year-old Mr Kaba, who was shot by a Metropolitan Police officer last month, asked police whether the young rapper asked for her in his last moments.

‘I want them to ask me, to tell me, how was Chris the last day?

‘How did Chris feel? What was the last words of Chris? Did he ask for me? Did he call for me? What did Chris say?

‘I wish this painful death must be the last – it must be the last.’

Speaking after handing in the letter, Mr Kaba’s cousin, Jefferson Bosela, said the family had stepped back from campaigning after viewing footage of the night in question because of how traumatic the experience had been.

‘They said there was a chase, they said there was a pursuit – there was no pursuit, there was no chase, there were no lights, there were no sirens,’ he said, in contrast to reports of the incident.

‘Viewing the footage and the body in one week – as you can imagine for anyone, that is traumatic, so we didn’t want the added pressure of the media trying to find out what was in the footage.’

He added he did not have faith Mr Sunak would respond to the letter, but urged the Prime Minister: ‘Just acknowledge we exist. If he’s unable to even acknowledge us, I don’t believe the British Government is for its people.’

Number 10 told MailOnline it is not providing a comment regarding the letter. 

Aisha Omishore, the grief-stricken younger sister of 41-year-old Mr Omishore, who died after jumping off a bridge having been tasered, said her brother’s memory had been ‘tarnished’ by inaccurate police reports of the incident.

Mr Omishore was initially reported to have been in possession of a screwdriver when police officers were called to Chelsea Bridge in west London on June 4.

The IOPC (Independent Office for Police Conduct) later said he had been holding a plastic and metal firelighter.

Ms Omishore said: ‘As a family, we find it unacceptable that the police were allowed to release a press statement containing facts they would have known to be incorrect at the time of release, and when they’d already referred themselves to the IOPC.

‘It tarnished my brother’s memory, it caused us unimaginable distress and pain, and just weeks of us having to try and defend our brother.’

The family say they have not yet had a chance to grieve properly because of the protracted process of seeking justice and accountability over Mr Omishore’s death.

His father, Alfred Omishore, paid tribute to his ‘caring, compassionate and artistically talented’ son who he said had been vulnerable and suffering a mental health crisis when police fired a Taser at him.

‘Only one police officer has been jailed for [a term of] eight years,’ Mr Omishore said outside Downing Street, referring to PC Benjamin Monk who was jailed for the unlawful killing of young footballer Dalian Atkinson.

‘Many people have died, many families are bereaved. This has to change.’

PC Monk was jailed last year, the first time in over 30 years that a British police officer had been convicted of manslaughter in the course of their duties, according to the IOPC.

While there have been 10 murder or manslaughter charges brought against officers since 1990, those accused have all been acquitted or the case against them has collapsed.

Melanie Leahy, whose 20-year-old son Matthew Leahy died while in the care of Essex mental health services in 2012, said fighting for a statutory public inquiry into state-related deaths was the only way to achieve justice for bereaved families.

‘The whole country needs to unite,’ she said.

Family members appeared tearful as they stood for pictures outside Number 10’s black door after delivering the letter, which calls for a meeting with Mr Sunak, the Home Secretary and the mayor of London.

Relatives hope to use the opportunity to discuss their concerns about ‘recurring issues in state-related deaths’ and demand changes to the way such deaths are handled.

The march to Downing Street was part of an annual event organised by the United Families and Friends Campaign (UFFC) – a group of those affected by deaths in police, prison and psychiatric custody – which has been staging protests for 24 years to demand justice for their loved ones.

Marcia Rigg, a UFFC organiser and sister of Sean Rigg – who died in police custody in 2008 – said on behalf of the campaign: ‘Families tirelessly campaign, when they ought to be grieving, for the truth of what happened to their loved one. 

‘We have no choice but to publicly challenge the judicial system, sadly at a very high cost to our mental health and well-being, because we do not want any other family to experience the same trauma and years of delays that we have.

‘The right to life, equality and proper justice have been continuously ignored or dismissed. This only serves to cause more heartache, distrust and lack of confidence in the systems causing and responding to deaths within our communities and the public.

‘We are taking this opportunity to inform the newly appointed Prime Minster of our objectives and demands for truth, justice, accountability and change, for an end to state killings, and the systematic patterns and failures which prevent justice and enable continued deaths.’

Lisa Cole, whose younger brother Marc was killed by a taser, has started an online petition calling for the banning of the weapon’s use against people suffering from mental health distress has received over 70,000 signatures. 

In a statement she wrote: ‘Tasers kill and they are being disproportionately used to target people who are experiencing Mental Health Issues and increasingly against racialised communities (who are over represented in mental health cases.) 

‘We are demanding that the Police use of these lethal weapons against people in mental health distress be banned.’

A spokesperson for the Mayor of London said: ‘The Mayor’s thoughts are with the families and friends who took part in the march today and who have lost loved ones. 

‘Every death in custody and every life lost following police use of force is a tragedy and each must be fully investigated, and findings acted upon.’

A Home Office spokesperson said: ‘Every death in police custody is a tragedy and we recognise the devastating impact on loved ones.

‘We must maintain a zero-tolerance attitude towards these rare, but devastating incidents, and where there are failings, appropriate action must be taken swiftly to address them.

‘Every case which involves a death in police custody is automatically investigated by the Independent Office of Police Conduct.’