It’s all too easy to blame Brexit for last week’s horrific assault in Croydon (Report, 3 April) that has left a teenage Kurdish-Iranian asylum seeker fighting for his life, but problems in this London borough are more longstanding.

In July 1992, Ruhullah Aramesh, an Afghan refugee living in the Thornton Heath area of the borough, was beaten to death in a racist attack by six white youths armed with iron bars and lumps of wood. Many other racist assaults occurred there during that decade. In 2011 a woman was filmed delivering a racist rant against black people and Poles on the Croydon tram. In January 2014 the English Defence League began targeting an Islamic community centre in Croydon as an “illegal mosque”. In June 2015 a woman had her hijab violently pulled off in a Croydon street. In October that year there was a high-profile immigration raid on Croydon works premises which resulted in seven arrests. Six of those arrested were transferred to detention centres pending their deportation.

The immediate responsibility for the recent sickening attack lies with the perpetrators, but a share of responsibility surely also may lie with every media outlet, political organisation and government institution that has fuelled a toxic atmosphere against minorities and asylum seekers. And that includes the last home secretary, Theresa May, who sent her vans with anti-immigrant threats around the streets of areas such as Croydon until they were withdrawn. Even the local Tory MP, Gavin Barwell, welcomed their withdrawal.

David Rosenberg

London

• On behalf of Young Roots, I want to express how devastated I am about the attack on the young asylum seeker in Croydon on Friday. We are heartbroken by this brutal crime. Many young asylum seekers have fled war, torture and other atrocities. They have survived dangerous journeys here and face loneliness, worries about the rest of their family, and the challenge of navigating the complex immigration system. A large number have post-traumatic stress disorder. Yet the young people we work with in Croydon are a delight. They are bright, warm, friendly and so keen to learn. They are endlessly supportive and kind.

Our thoughts are with the victim of this alleged hate crime, and we will continue to work hard to support the young refugee and asylum-seeking community in Croydon to be safe and come to terms with this terrible attack.

Jo Cobley

Director, Young Roots – helping young refugees reach their potential

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