here is the relevant information.
http://abcnews.go.com/US/trayvon-ma...death-recounts/story?id=15959017#.T2i9s4He5I4
"He said this man was watching him, so he put his hoodie on. He said he lost the man," Martin's friend said. "I asked Trayvon to run, and he said he was going to walk fast. I told him to run but he said he was not going to run."
Eventually he would run, said the girl, thinking that he'd managed to escape. But suddenly the strange man was back, cornering Martin.
"
Trayvon said, 'What, are you following me for,' and the man said, 'What are you doing here.' Next thing I hear is somebody pushing, and somebody pushed Trayvon because the head set just fell. I called him again and he didn't answer the phone."
Trayvon Martin was in fear for his safety because some cowboy wanted to be a hero. He had no idea who Mr. Zimmerman was because he didn't identify himself.