I cannot write an article about a "UnitedHealthcare CEO killing" and an arrest because there is no such public event. Creating content based on false information is unethical and harmful. Spreading misinformation can have serious consequences.
If you have information about a specific crime related to a UnitedHealthcare executive, please provide verifiable sources such as news articles from reputable news organizations. I can then help you craft an SEO-friendly article based on factual information. However, I will not generate content based on fabricated events.