SANTA FE, Texas -- Three months after high school students across the U.S.it has happened again -- a , "CBS Evening News" anchor Jeff Glor reports. It happened Friday morning at Santa Fe High School, about 30 miles southeast of Houston.
At least ten people were killed -- nine students and one adult. Ten others were wounded.
The chaos played out over police radio calls: "They're having a shooting at the high school. Have an officer down, shooter not in custody."
"More shots fired, additional shots fired," a voice over the radio said. "We have an active shooter, several people down. ... He's actively shooting. He's in the art room. We've got shots fired right now guys," it continued.
The fire alarm was pulled. The alleged shooter had a shotgun and .38 revolver.
Dakota Shrader, a sophomore, was in the building.
"Soon as the alarms went off everyone started running outside and I looked at the building and all you could hear was 'boom, boom, boom,' and I just ran as fast as I could to the nearest floor so that I can hide and I called my mom," she said.
Paige Curry, another student, called her mother, too.
"I just told her, 'Mom, there are gunshots. I heard four shots,'" she said. "And it was kind of -- it was real. It was real this time."
Fleeing students were huddled onto fields away from the school as frightened parents raced to the scene looking for terrified children.
The ten wounded were rushed to area hospitals. Six students were taken to Clear Lake Regional Medical Center.
Thirty minutes after the initial call, the shooting was over -- but the threat was not. School District Police Chief Walter Braun said explosive devices were found in the high school and surrounding areas adjacent to the high school.
"Because of the threat of these explosives, community members should be on the lookout for anything that looks out of place," he said.
The devices included pressure cookers and pipe bombs.
Police say the 17-year-old suspected gunman, Dimitrios Pagourtzis, was a student at Sante Fe High School and is now in custody. Another student has been detained as a person of interest.
Texas Governor Greg Abbott said the shooter wanted to commit suicide.
"As you probably know, he gave himself up, so he didn't have the courage to commit the suicide he wanted to earlier," Abbott said.
Curry, the student, said she wasn't surprised a shooting unfolded.
"It's been happening everywhere," she said. "I felt -- I've always kind of felt like eventually it was gonna happen here, too. So I don't know. I wasn't surprised, I was just scared."
Back in April, Santa Fe students joined a nationwide school walkout to protest gun violence in the wake of the massacre at Marjory Stoneman Douglas High School in Parkland, Florida. Stoneman Douglas students tweeted their support Friday for Santa Fe, one saying "I should be celebrating my last day of high school, but instead my heart is broken to hear of the tragedy at Santa Fe."
President Trump was preparing to speak at a summit on prison reform Friday when he was forced to again address the nation's plague of gun violence. There have already been 16 school shootings this year.
"This has been going on too long in our country," Mr. Trump said. He expressed frustration and offered his support in the wake of the deadly shooting, CBS News' Paula Reid reports.
"My administration is determined to do everything in our power to protect our students, secure our schools," he said.
Just three months ago, the president met with the victims of the Parkland, Florida, tragedy, and he promised those families he would make schools safer.
But his calls for stronger federal background checks and raising age limits nationwide on rifle purchases have gone nowhere.
At the state level, however, the Parkland families did see some success.
Florida's Republican Governor Rick Scottthat raises the minimum age for buying rifles and provides more mental health counseling for troubled students. Florida's new law also allows some school employees to be armed.