The numbers reliably considered to be political prisoners have risen sharply in the last four years. In May 2016, the Memorial Human Rights Centre put the total at 89. By May 2017, Memorial considered there were at least 117 political prisoners or prisoners of conscience (66 accused of belonging to the Muslim organisation Hizb ut-Tahrir al-Islami which has been banned in Russia since 2010). Among these prisoners is also human rights defender Emir-Usein Kuku from Crimea who was accused of belonging to Hizb ut-Tahrir although he denies any involvement in this organization. Amnesty International has called for his immediate liberation.