The leader of an advocacy group for black and minority ethnic women has hit out at an “institutionally racist system” after an assault case against her and two friends was dropped.

Selma Taha, 52, the executive director of Southall Black Sisters, had been charged along with Divina Riggon, 42, and Danae Thomas, 53, with assaulting a woman in King’s Cross Underground station.

But they claimed they were the victims of a violent racist attack.

As relieved as I am about the decision being in our favour, this has been hard-fought and I continue to feel aggrieved at the treatment my sisters and I have received

They had been due to attend a three-day trial at Highbury Corner Magistrates’ Court from Wednesday, but the case was formally discontinued because prosecutors no longer had a realistic prospect of conviction.

Around 40 supporters cheered and waved placards as the trio left the court building raising their arms aloft.

Ms Taha shed tears as she said: “As relieved as I am about the decision being in our favour, this has been hard-fought and I continue to feel aggrieved at the treatment my sisters and I have received.

“From being subjected to vile racist slurs and significant injuries on public transport in the presence of an off-duty police officer I expected more responsibility and a duty of care from, to being disbelieved and criminalised by the CPS for challenging the racist abuse, the past 10 months have reaffirmed my lack of faith in the system and served as a daily reminder of the challenges we are up against as black, minoritised and migrant victim-survivors seeking a just response from an institutionally racist system.”

All three were accused of assault by beating in the central London Tube station on September 29 last year.

Ms Riggon was also charged with harassment and Ms Thomas was accused of racially aggravated harassment, but both counts were discontinued.

Barrister Rajiv Menon KC, who represented Ms Taha and Ms Thomas, said: “This decision should have been made nine months ago, this prosecution should never have been brought.

“Danae, Selma and Divina were victims of a racist attack on the Tube and whilst this kind of prosecution was extremely common 20, 30, 40 years ago, it should not be happening any more in 2024, it is an outrage.”

Southall Black Sisters said the complainant in the case had accepted a caution for racially aggravated conduct under the Public Order Act and no further action was taken.

Its petition, which called on the Crown Prosecution Service (CPS) to drop the charges, had surpassed 36,000 signatures.

A CPS spokesperson said: “We have a duty to keep all cases under continuous review and following information received in the past few days, we decided that there was no longer a realistic prospect of conviction, and these charges were discontinued.”