UPDATE: The gunman in the school shooting has been identified as Adam Lanza, 20. Earlier it was reported that his older brother Ryan Lanza was a suspect, but that was corrected.
A law enforcement official says the boys' mother, Nancy Lanza, works at the school as a teacher.
Speaking on condition of anonymity, the official said the suspect is dead from a self-inflicted gunshot wound.
The official spoke on the condition of anonymity because the source was not authorized to speak on the record about the developing criminal investigation.
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