The UK has thousands of people in modern slavery -- and in London it's getting increasingly worse

 Anti-slavery activists rally outside Parliament on October 18, 2013, in London, England.

(CNN)The number of identified victims of modern slavery and human trafficking in London has risen more than tenfold in the space of five years, according to a new report which analyzes police data.

Data from London's Metropolitan Police shows a 1,154% increase in the number of recognized victims of modern slavery -- from 187 referrals in 2013 to 2,346 in 2018.
More than 30% of the 5,143 people referred by the Home Office in 2017 for support were in London -- nearly three times higher than any other region or country in the UK, according to a letter from the London Assembly's police and crime committee.
    In October, the Local Government Association said that the number of council referrals of suspected child victims of modern slavery in England had risen by 807% between 2014 and 2018.
    London needs to have a "more coherent" strategy to tackle modern slavery and human trafficking, the London Assembly's police and crime committee said in a letter to the deputy mayor for policing and crime, Sophie Linden.