Even though paraphrasing and summarizing are supposed to be different, their definitions overlap.
Paraphrazing means rewording something that was said or written by someone else by using your own words. Summarizing means condensing what was said or written by someone by reducing it to its main idea(s), eliminating extra information. When summarizing, it's common for people to also paraphrase, since it may help rewrite the idea in a shorter way.
The narrator was guilty that he suffocated and dismembered the old man. When the police arrived and had a chat with him, the guilt got to him and he confessed his crimes.