AP Photo/Jessica Hill
Parents leave a staging area after being reunited with their children following a shooting at the Sandy Hook Elementary School.
Authorities released a summary of their report last month that said investigators weren't able to determine a motive for Adam Lanza's massacre. He killed 20 school children, six adults, and his own mother before shooting himself in the Newtown, Conn. school.
The full report is several thousand pages long and contains additional evidence from the investigation. The case is now closed.
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