Complex sentence: The first group was the Hutu hardliners, centred around the family of Agathe Habyarimana, were represented by the CDR, as well as extremists within the president's own MRND party.
Split into simpler sentences: The first group was the Hutu hardliners, centred around the family of Agathe Habyarimana. They were represented by the CDR, as well as extremists within the president's own MRND party.