Ryan Lanza on the news.
"Newtown: An American Tragedy" goes on sale Dec. 10 and contains new details about the Dec. 14 shooting.
Police reportedly questioned Ryan for hours in Hoboken, according to the book. They asked him if he knew what Adam did.
When asked about the last time he spoke to Adam, Ryan told police that he hadn't spoken to him in more than a year. When they asked him why the brothers didn't speak to each other anymore, Ryan said Adam is "sick" and "[doesn't] talk to anyone."
"Do you have any idea why he did this?" police asked.
Ryan responded: "No. I don't know him anymore."
Police and media incorrectly identified Ryan Lanza, a then-24-year-old employee at Ernst & Young, as the possible shooter in the chaos that followed the massacre. Adam apparently had Ryan's driver's license on his person at the scene of the shooting.
Once Ryan saw his name on the news in connection with the shootings, he immediately left his Times Square office and headed back to his apartment in New Jersey. On the way, he posted on his private Facebook page: "IT WASN'T ME I WAS AT WORK IT WASN'T ME."
CNN reported Ryan's name more than three hours before issuing a correction on the air.
Ryan got back to his Hoboken apartment at about 3 p.m., and a few minutes later, police handcuffed him and put him in a squad car. They searched his apartment and looked into his phone and computer records.
Adam killed 20 children and six adults before committing suicide in a classroom. He also shot and killed his mother Nancy before leaving his house for Sandy Hook that day.