WASHINGTON (AP) ? The suspect in the Connecticut school shootings is Adam Lanza, 20, the son of a teacher at the school where the shootings occurred, a law enforcement official said Friday. ABC News reportsthatneighbors described Adam Lanzaas ?odd? and displaying characteristics associated with mental illness. A second law enforcement official says the boy's mother, Nancy Lanza,is presumed dead. Lanza'sgirlfriend and another friend are missing in New Jersey, the official also said. Police say 27 people were killed in the shooting at a Connecticut elementary school, including the gunman, and one person died at another scene. The dead at the school include 20 children. Adam Lanza's older brother, Ryan, 24, of Hoboken, N.J., is being questioned by police, said the first official. Earlier, a law enforcement official mistakenly transposed the brothers' first names. Both officials spoke on the condition of anonymity because they were not authorized to speak on the record about the developing criminal investigation. The first official said Adam Lanza is dead from a self-inflicted gunshot wound. According to the second official, the suspect drove to the scene of the shootings in his mother's car. Three guns were found at the scene ? a Glock and a Sig Sauer, both pistols ? and a .223-caliber rifle. The rifle was recovered from the back of a car at the school. The two pistols were recovered from inside the school. Robert Licata said his 6-year-old son was in class when the gunman burst in and shot the teacher. "That's when my son grabbed a bunch of his friends and ran out the door," he said. "He was very brave. He waited for his friends." He said the shooter didn't utter a word. Stephen Delgiadice said his 8-year-old daughter was in the school and heard two big bangs. Teachers told her to get in a corner, he said. "It's alarming, especially in Newtown, Connecticut, which we always thought was the safest place in America," he said. His daughter was fine. Mergim Bajraliu, 17, heard the gunshots echo from his home and ran to check on his 9-year-old sister at the school. He said his sister, who was fine, heard a scream come over the intercom at one point. He said teachers were shaking and crying as they came out of the building. "Everyone was just traumatized," he said. Mary Pendergast, who lives close to the school, said her 9-year-old nephew was in the school at the time of the shooting, but wasn't hurt after his music teacher helped him take cover in a closet. Richard Wilford's 7-year-old son, Richie, is in the second grade at the school. His son told him that he heard a noise that "sounded like what he described as cans falling." The boy told him a teacher went out to check on the noise, came back in, locked the door and had the kids huddle up in the corner until police arrived. "There's no words," Wilford said. "It's sheer terror, a sense of imminent danger, to get to your child and be there to protect him." Meanwhile, former Jersey Journal staff writer Brett Wilshe said he has spoken with Ryan Lanza of Hoboken, who told Wilshe the shooter may have had Ryan Lanza's identification. Ryan Lanza has a Facebook page that posted updates Friday afternoon that read that "it wasn't me" and "I was at work."