Complex sentence: Shazia Khan, a daughter of Saleem, claimed that her brother had received increasingly threatening letters purporting to be from the EDL; one of them stated: "One letter said:" It has come to our attention that you are training terrorists at your premises.
Split into simpler sentences: Shazia Khan, a daughter of Saleem, claimed that her brother had received increasingly threatening letters purporting to be from the EDL. One of them stated: It has come to our attention that you are training terrorists at your premises.