The planned release of thousands of pages of state police documents from the investigation into last year's Newtown school massacre could shed light on the world of the 20-year-old gunman.
Prosecutors issued a summary of the investigation last month that portrayed gunman Adam Lanza as obsessed with mass murders, but concluded that Lanza's motives for the massacre might never be known.
The report referred to items found on a computer at Lanza's house that included writings that detail relationships, personal beliefs, a daily schedule, desires and goals.
Lanza gunned down 20 first-graders and six educators with a semi-automatic rifle at Sandy Hook Elementary School on Dec. 14, 2012, after killing his mother inside their home. He committed suicide as police arrived at the school.
The documents will be released Friday.
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