Report: Zimmerman told police teen punched him before fatal shooting

The core of Trayvon Martin's story has been told again and again in recent days -- about how the 17-year-old went out to a Sanford, Florida, convenience store, only to be killed on his way back to his father's fiance's home.

Yet one month later, questions persist as to exactly how and why that happened. The man who admitted shooting the teen has not been charged in connection to the case, much to the dismay of Martin's parents and thousands of strangers nationwide who've rallied behind them.

On Monday, the story continued to gain both complexity, and clarity, thanks to details of the account that Martin's shooter gave to police after the shooting.