The trial for a southwest Florida man accused of killing a young couple around Christmas three years ago has started.

The slayings garnered national attention because the couple’s 2-year-old son was heard on a 911 call and then was found holding the phone when police arrived. The boy had not been harmed.

Fred Dewitt Cooper Jr. is charged with armed burglary and two counts of first-degree murder. He has pleaded not guilty and his attorneys said during opening arguments Friday that the couple had a turbulent relationship.

Prosecutors say witnesses, DNA and other evidence will show Cooper is responsible for killing Steven and Michelle Andrews. She had been beaten and strangled. Her husband was shot in the head.