"He was amazing. He ran after the mugger like a man possessed -- a real hero," the source said.
The 22-year-old Osbourne told the News of the World his impromptu crime-fighting decision was merely the "right thing to do" in the circumstances, the Telegraph said.
"I could see the girl was in trouble; it just felt like the natural thing to do. I'm glad it turned out OK," the former star of the reality TV series "The Osbournes" said.
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