“This was the claim in the Trayvon Martin case.”
It was a false claim. The confrontation was initiated by Martin. Here, the white guys, armed with shotguns, initiated the contact.
Zimmerman followed Martin. With a gun.
Here's part of the Wikipedia account.
“About two minutes into the call, Zimmerman said, “he's running”.[51] The dispatcher asked, “He's running? Which way is he running?”[52] Noises on the tape at this point have been interpreted by some media outlets as the sound of a car door chime, possibly indicating Zimmerman opened his car door.[53] Zimmerman followed Martin, eventually losing sight of him.[51] The dispatcher asked Zimmerman if he was following him. When Zimmerman answered, “yeah”, the dispatcher said, “We don't need you to do that.” Zimmerman responded, “Okay.”[54] Zimmerman asked that police call him upon their arrival so he could provide his location.[51] Zimmerman ended the call at 7:15 p.m.
After Zimmerman ended his call with police, a violent encounter took place between him and Martin. It ended with Zimmerman fatally shooting Martin 70 yards (65 m) from the rear door of the townhouse where Martin was staying.”