Police found a smashed computer hard drive along with the gun safe in the room they believed to be Adam Lanza's bedroom, court papers have revealed.
One person interviewed by the FBI described Lanza as "a shut-in and avid (computer) gamer who plays Call of Duty amongst other games."
FBI agents were also told the Sandy Hook Elementary School was his "life."
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In her message Theresa May praised the "inspirational bravery" and "unbreakable spirit" of Mancunians in the wake of the blast.
ITV News has obtained exclusive footage of the moment armed police raided a house believed to be linked to the Manchester suicide bomber.
The Manchester Evening News set up a JustGiving page asking people to support the families of those affected by the suicide bombing.