A star witness will be revealed by prosecutors in the George Zimmerman murder trial for the first time on Tuesday, the girl Trayvon Martin was talking with in the last minutes of his life. The teenage girl, known as Witness #8 until now, was due to testify about what Martin, the unarmed Black 17-year-old shot and killed by Zimmerman last year, told her what he saw that night.

Identified in court on Monday only as Rachel, a friend of Martin from Miami, she received a running account about what was happening, starting when he noticed a man, Zimmerman, watching him in the gated central Florida community he was visiting.

Zimmerman, 29 and part Hispanic, was a neighborhood watch volunteer in the Retreat at Twin Lakes community in Sanford at the time of the February 26, 2012, killing. He has pleaded not guilty to second-degree murder and could face life imprisonment if convicted.