"I know you are ... but I need you to stay on the phone," she replied.
She asked if he was under the influence of drugs or alcohol, which he denied, and what he planned to do at the train station. He didn't know.
When he indicated police had arrived, the call taker told him to give them a quick wave and that she would stay on the line until she heard the officers speaking.
Nearing the end of the call he repeated: "I can't believe it happened."
Two constables arrived and Martin Marinovich was arrested for assault.
The Crown alleges Martin Marinovich murdered his mother after likely arguing with her in the cramped and dirty Oratia home they shared.
"Ms Marinovich would rely a great deal on her son," Crown prosecutor Elena Mok said.