Adam Lanza, the 20-year-old who killed 20 children and six adults at Sandy Hook Elementary School in Newtown, Connecticut this morning, was "obviously not well," a relative told ABC News.
Family friends in Newtown also described the young man as troubled and described his mother Nancy as very rigid. "[Adam] was not connected with the other kids," said one friend.
Late today, police said Nancy Lanza's body was found in the family home. According to sources, Lanza shot his mother in the face, then left the house armed with at least two semi-automatic handguns and a semi-automatic rifle.
State and federal authorities believe his mother may have once worked at the elementary school where Adam went on his deadly rampage, although she was not a teacher, according to relatives, perhaps a volunteer.
As part of the investigation authorities searched the New Jersey apartment of Adam's older brother Ryan in Hoboken, New Jersey.
Police had initially identified Ryan as the killer, until he sent out a series of Facebook posts saying it wasn't him and that he was at work all day.
Sources told ABC News that Ryan, 24, works as a senior person in Ernst and Young's tax practice in Manhattan.
"He's a tax guy and he is clean as a whistle," a source familiar with his work said.
Ryan has worked at the firm 4 years.
Today the NYPD and FBI went to Ernst & Young and removed Ryan's laptop and other possessions, which is part of the normal investigative process.
Officials were interviewing Ryan and his father, but neither person was under any suspicion, multiple sources said.