South Yorkshire Police says it wants to reassure residents that a full investigation is under way into malicious communications sent to addresses in Sheffield. Officers say they have received reports of three letters encouraging people to take part in “Punish a Muslim Day”. According to reports similar letters have been delivered in other cities including Bradford, Leicester, London, and Cardiff. A national operation has been launched to investigate the letters, co-ordinated by counter terrorism officers. Sheffield Live! reporter Baillor Jalloh spoke to Zameer Khan, secretary at Madina Mosque.