The London mayor also raised concerns with the home secretary that overcrowding and poor protection in hotels hosting asylum seekers has led to reports of sexual assaults on children. Earlier, it emerged that Braverman was facing a legal challenge over conditions at Manston in Kent, which houses thousands of people seeking asylum in the UK. On Thursday, the Home Secretary flew into Manston in a chinook helicopter to visit the center for the first time. The Home Office said more than 1,000 people had moved out of Manston in the past five days. At one point, 4,100 people, including children and pregnant women, lived in a space designed for 1,600. The Guardian reported on Wednesday that a group of asylum seekers from the Kent facility had been left at Victoria train station with nowhere to stay and many were wearing flip-flops. On Thursday, it emerged that a teenage boy was allegedly raped by a man in his 30s at a hotel hosting refugees in east London. In a letter to Braverman, Khan wrote: “I am appalled by the disgraceful reports that the Home Office has abandoned dozens of asylum seekers from the Manston immigration center in central London, cold, hungry and homeless. “I am also deeply concerned by reports of child sexual assault and severe overcrowding in hotels used by the Home Office to house asylum seekers. “This situation is a clear abdication of your department’s statutory responsibilities and duties to protect those in its care and represents a complete dereliction of duty. The Home Office must carry out an urgent and thorough review to ensure that the ongoing crisis is addressed and that this can never happen again. “I would also like to ask you to confirm whether asylum seekers have previously been abandoned without accommodation.” Lawyers on behalf of the charity Detention Action and a woman held at the facility in Kent sent an urgent precautionary action letter to the Home Office on Tuesday. It represents the first action against the Home Secretary for “unlawful treatment of people detained in the premises”. The pre-action letter, sent by Duncan Lewis’ lawyers, said the woman, from a non-European country, was “unlawfully detained by the Home Secretary at the Manston facility in grossly defective conditions”. The complaint also includes “serious threats to the safety of children”, the charity said. Archie Bland and Nimo Omer take you to the top stories and what they mean, free every weekday morning Privacy Notice: Newsletters may contain information about charities, online advertising and content sponsored by external parties. For more information, see our Privacy Policy. We use Google reCaptcha to protect our website and Google’s Privacy Policy and Terms of Service apply. Concerns raised by the woman about the site near Ramsgate include “the routine extension of detention beyond statutory time limits. failure to observe basic child protection measures; women and children sleeping next to adult men with whom they are not related. inadequate or non-existent access to legal advice for those detained; and exposure to infectious diseases due to overcrowding and poor sanitation,” the charity said. Four chairmen of parliamentary committees stepped up pressure on the home secretary to explain how the government would control the situation at the Kent facility and the immigration crisis more generally. In a joint letter to Braverman, the chairs of the home affairs committee, the justice committee, the joint human rights committee and the women and equalities committee expressed their deep concerns about the deplorable conditions at Manston, asking what could be done to address the current situation and avoid overcrowding in the future. Earlier on Thursday, Graham Stuart, a government minister, admitted the site was not operating legally and that “none of us are comfortable with it”. But he tried to blame an “unacceptable increase” in small boat crossings for the problem, adding that “the system is struggling to cope”. The Home Secretary avoided questions from the press during her visit to Western Jet Foil in Dover – the scene of Sunday’s petrol bomb attack – amid concerns about growing far-right activity.