Complex sentence: The British wing of Hizb ut-Tahrir in the early 90's was known for its charged and sometimes abusive character, this was largely the result one of its ex-chairmen Omar Bakri Muhammad, who then set up the more extreme al-Muhajiroun organisation in 1996.
Split into simpler sentences: The British wing of Hizb ut-Tahrir in the early 90's was known for its charged and sometimes abusive character. Its chairman was Omar Bakri Muhammad, who left to set up the more extreme al-Muhajiroun organisation in 1996.