The first official says Adam Lanza's older brother, 24-year-old Ryan Lanza,, of Hoboken, N.J., is being questioned by police. An earlier report from a law enforcement official mistakenly transposed the brothers' first names.
Both officials spoke on the condition of anonymity because they were not authorized to speak on the record about the developing criminal investigation.
The first official said shooter Adam Lanza is dead from a self-inflicted gunshot wound.
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