When Nancy took her older son, 24-year-old Ryan Lanza, to see a concert in New Orleans, Adam didn't join them.

WSJ: Portraits of Newtown Victims

Ryan Lanza was taken into custody for general questioning Friday from a home in Hoboken, New Jersey, according to three law enforcement officials.

CNN: STORY HIGHLIGHTS

Adam Lanza's brother, Ryan, works as a certified public account in New York, the aunt said.

CNN: STORY HIGHLIGHTS

Earlier Friday, a law-enforcement official incorrectly identified the suspected shooter as Mr. Lanza's 24-year-old brother, Ryan.

WSJ: Dozens Killed in Newtown, Connecticut, School Shooting