A day after a Murrysville, Pennsylvania, teen allegedly rampaged through his high school's hallways, stabbing wildly with two kitchen knives, the first hints of a possible motive began to emerge.
The attorney for 16-year-old Alex Hribal raised the specter that his client may have been bullied, telling CNN affiliate WTAE in Pittsburgh on Thursday that it looks like some kind of "bullying event" may have played a role.
"I think a lot of things have happened. I don't want to comment specifically, but I think there are some things that occurred that led to where we are today," Patrick Thomassey said.
But an FBI official, familiar with the investigation, discounted bullying as a motive.
"He was disaffected but not bullied," the official said on condition of anonymity.
Hribal, a sophomore, was charged as an adult and faces four counts of attempted homicide and 21 counts of aggravated assault in connection with Wednesday's attack at Franklin Regional Senior High School that left 20 teens and one adult wounded.
Some classmates at the school describe Hribal as having few friends and being quiet but also as a "really nice kid," a description that contradicts the image of a knife-wielding teen offered by authorities.
Murrysville Police Chief Tom Seefeld said investigators haven't yet made sense of the mass stabbing.
"We believe, through the investigation, that this was random," he told CNN's "New Day." "We don't have anybody that was targeted, as far as we know at this point."
Still, there were more questions than answers about what led the teen to allegedly attack his classmates with two steak knives believed to have been taken from his family's home.
"We're going to try to figure out what happened here. Obviously, there's a problem. You just don't leave and go to school, and do what he did yesterday," Thomassey told CNN earlier in the day.
There is "some deep-rooted problem somewhere that caused him to do this."
One thread that police are looking into is the possibility that there was a phone threat the night before, Seefeld said.
But no immediate evidence has been found to confirm such a call, and Thomassey discounted the allegation.
"He was home all night the night before this occurred, with his parents," he told WTAE. "They did not see him on the phone arguing with anybody."
The FBI has seized electronics belonging to Hribal, including a computer and cell phone, and will analyze them for any clues, the police chief said.
In a telephone call Thursday, President Barack Obama assured Franklin Principal Ron Suvak that the FBI will continue to assist in the investigation, the White House said.
See more on this story at CNN.com.
"All right, good night."
Those are the last words heard from the cockpit of Malaysia Airlines Flight 370, said Zulazri Mohd Ahnuar, Malaysian civil aviation officer.
Who said them? Was it the captain or his first mate? Or someone else in the cockpit with them?
Since MH 370 went missing Saturday, there have been more questions than answers, including about the pilots.
Malaysian investigators are considering the possibility that one of them was involved in its disappearance, the transportation minister said Friday.
Information from U.S. officials indicated that the Boeing 777-200ER passenger jet may have flown for five hours after last contact with the pilots.
The duty of all pilots is to aviate, navigate and communicate, in that order, an aviation expert has told CNN.
Someone may have kept aviating, but either they couldn't - or wouldn't - communicate.
This is what we know about the 50-year-old pilot captain and his 27-year-old first mate.
See the full story on CNN.com.
By Elizabeth Stuart and Pamela Brown
His wounds as an Army Ranger in Afghanistan in 2009 left him in the fight of his life - a fight for his life, for sheer survival.
And when his story was told by the President of the United States, that story brought a packed house in the U.S. Capitol to its feet for a standing ovation.
"Cory Remsburg never gives up, and he does not quit," President Barack Obama declared to the nation in his State of the Union address in January.
Being singled out for presidential recognition made Remsburg overnight the most recognizable veteran in the country, a position he's not entirely comfortable with. But he says he's OK with the attention as long as it brings attention to all wounded veterans.
"There are other people who would have quit a long time ago and would have been happy in their wheelchair. Me? Oh, no," he says in an interview on CNN's "New Day" on Thursday.
American Christian missionary Kenneth Bae has been imprisoned in North Korea for 15 months– his sister, Terri Chung– says that he's now the longest American detained there in recent history. She says her family is very scared about what's going to happen next after her brother's video-taped statement, CNN's Pamela Brown reports.
The American missionary, who has been held in North Korea for more than a year, read a statement before cameras in a Pyongyang hospital.
In the video he says "I would like to plea with the U.S. government, press and my family to stop worsening my situation by making vile rumors against North Korea and releasing materials related to me, which are not based on the facts." (translated)
Bae goes on to say that he committed a “serious crime” against North Korea’s government and that he did not experience any human rights abuse.
Experts say these new images of Bae could be a positive sign, given that North Korea’s history of coercing confessions before releasing their captives.
"The fact that they've paraded him out and gone through this farce suggests that they have some kind of demand in mind," says Dr. Jeffrey Lewis, Director of East Asia Non-Proliferation Program and an East Asia Scholar at the Monterey Institute of International Studies
Kenneth Bae's sister asks that President Obama and Secretary Kerry take immediate action to bring her brother home. Experts say Bae's confession follows North Korea's pattern of exacting false "confessions." Most recently– 85-year-old Merrill Newman, a Korean War veteran, was freed from the country after he says he was forced to give a false confession.
For background and updates as the story develops, go here.