Little Is Known About Connecticut School Shooter Adam Lanza

School Shooting

(CNN) — Who was Adam Lanza? He’s a 20-year-old Connecticut man, but other than his age, the picture of him is blurry. But the details of what law enforcement officials say he did Friday are all too vivid.

That morning, Adam Lanza burst into Sandy Hook Elementary School in Newtown, Connecticut, dressed in “black battle fatigues and a military vest” and began firing, according to a law enforcement source. By the time he was done, 26 were dead — 20 of them young students.

The bloodshed ended when Lanza’s own life did. He was found dead in a classroom with two firearms, a Glock and Sig Sauer. Another gun, a 223 Bushmaster, was found nearby in a car.

The massacre left people in the Connecticut community, around the country, around the world asking questions. Who was this man, and why did he do this?

As of early Friday evening, authorities had offered few details about Adam Lanza. He had no known criminal record, a law enforcement official said.

His mother and father were divorced. His father had remarried and lived not too far from Newtown, an official said.

Adam Lanza had a brother, too. Ryan Lanza, 24, was seen being taken away from a residence in Hoboken, New Jersey, by police for questioning Friday .

The Lanza family home in Newtown, meanwhile, became a crime scene after the shooting. Yellow crime tape surrounded it as law enforcement officers streamed in and out.

Around 3:15 p.m., an ambulance came and went. Adam’s mother Nancy Lanza — a teacher at Sandy Hook Elementary — was found dead at the family’s Newtown residence, a law enforcement source said.

After news of the shooting broke on Friday morning, neighbors said they were told to evacuate their homes right away. Some were escorted back to their homes, albeit temporarily.

These Newtown residents described their terror and fear but did not reveal much about the Lanza family, saying they were unfamiliar with them.

Beth Israel said her daughter was in the same class at Newtown High School with Adam Lanza, who lived six houses away.

“He was troubled for sure for a long time,” Israel said on Twitter.

CNN’s Susan Candiotti and Mary Snow reported from Newtown, Connecticut. CNN’s Tim Lister, Terry Frieden and John King also contributed to this report. CNN’s Greg Botelho wrote this story from Atlanta.

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