Complex sentence: He then returned to the kitchen and, when Maude told him not to shoot any birds, fatally shot her in the head before firing twice more into her back--with some accounts claiming that Maude Kemper also suffered multiple post-mortem stab wounds with a kitchen knife.
Split into simpler sentences: He then returned to the kitchen and, when Maude told him not to shoot any birds, fatally shot her in the head before firing twice more into her back. Some accounts also state that Maude Kemper also suffered multiple post-mortem stab wounds with a kitchen knife.