reporter: the shooting happened six blocks away from where a 7-year-oldl shot trick-or-treating on halloween she survived and the 15-year-old was arrested police say aguilar may have been a victim of mistaken identity. come forward and admit your wrongs because, you know what he probably would have been the one saving you instead of him being on the table. reporter: a nurse committed to helping save lives unable to save his own ron mott, nbc news, chicago. overseas tonight, hong kong is bracing for more violence after the standoff between anti-government protesters and riot police has escalated to new heights nbc s richard engel with the story and a warning. some of the images are disturbing reporter: students at a hong kong university were barricading themselves on campus, digging up the streets to slow down riot police to ir calls fr democratic reforms and more independence from china. this once gleaming city is descending
associate kline calling professor of psychology at harvard medical school. thank you guys for joining us. mike, i want to devote my first question to you. sure. in this case, like in new town, the shooter was living with his mother, but aguilar s mother said she saw no signs of any of this. how can someone in such close proximity not see anything unusual? well, i have a hard time believing it also, but many times, don, people who are closest to let s say the shooter, they might not recognize any signs, and, you know, what was the family dynamic going on at the time with her and her son? and, you know, he said he bought the gun for home defense. had he discussed that with her? did she not find it unusual that he had so much ammunition because apparently during the search warrant they went to the house and found a large amount of ammunition? did she not find that unusual, and i would like to know if he was exhibiting any signs, ever had any history of any mental illness, because ap
erin burnett outfront starts right now. thank you. next, new details about the gunman who terrorized a maryland mall this weekend. what he wrote in his journal and what a friend says he planned to do today. plus, hillary clinton reveals her biggest regret as secretary of state and starts to distance herself from president obama. and why are some people calling the grammys racist? let s go outfront. good evening, everyone. thanks so much for joining us. i m don lemon in for erin burnett. tonight, what made a maryland teenager open fire at a mall this weekend terrorizing employees and customers? we re learning more tonight about 19-year-old darren aguilar who shot and killed two
employees at a skateboard shop before turning the gun on himself. his mother calls him a gentle, sweet kid but police say aguilar s journal expressed general unhappiness with his life. the gun shop where aguilar purchased the gun tells cnn that the 19-year-old visited the shop twice in december. on his first visit aguilar purchased a shotgun for $430 in cash, plus two boxes of ammunition and a couple weeks later aguilar returned for another box of shut gun shells, but the big question still remains. why did he open fire in the first place? joe johns is in columbia, maryland, with the very latest. reporter: saying he wanted something for home defense, darian aguilar legally purchased a mossberg .50012 gauge shotgun and 48 shotgun shells. the owner of the united gun shop tells cnn there were no red flags. both times aguilar visited the shop he was accompanied by a friend. today at the scene of the shoot a makeshift memorial not far from the place where 21-year-old
employees at a skateboard shop before turning the gun on himself. his mother calls him a gentle, sweet kid but police say aguilar s journal expressed general unhappiness with his life. the gun shop where aguilar purchased the gun tells cnn that the 19-year-old visited the shop twice in december. on his first visit aguilar purchased a shotgun for $430 in cash, plus two boxes of ammunition and a couple weeks later aguilar returned for another box of shotgun shells. but the big question still remains. why did he open fire in the first place? joe johns is in columbia, maryland, with the very latest. reporter: saying he wanted something for home defense, darion aguilar legally purchased a mossberg .520-gauge shotgun and 48 shotgun shells. the owner of the united gun shop tells cnn there were no red flags. both times aguilar visited the shop he was accompanied by a friend. today at the scene of the shoot a makeshift memorial not far from the place where 21-year-old brianna benlolo and 25-y