CHARLOTTE, N.C. >> A North Carolina college student tackled a gunman who opened fire in his classroom, saving others’ lives but losing his own in the process, police said today.

Riley Howell, 21, was among the students gathered for end-of-year presentations in an anthropology class at the University of North Carolina-Charlotte when a gunman with a pistol began shooting students. Howell and another student were killed; four others were wounded.

Charlotte-Mecklenburg Police Chief Kerr Putney said Howell “took the assailant off his feet,” but was fatally wounded. He said Howell did what police train people to do in active shooter situations.

“You’re either going to run, you’re going to hide and shield, or you’re going to take the fight to the assailant. Having no place to run and hide, he did the last. But for his work, the assailant may not have been disarmed,” Putney said. “Unfortunately, he gave his life in the process. But his sacrifice saved lives.”

The father of Howell’s longtime girlfriend said news that he tackled the shooter wasn’t surprising. Kevin Westmoreland, whose daughter Lauren dated Howell for nearly six years, said Howell was athletic and compassionate — and would have been a good firefighter or paramedic.

“If Lauren was with Riley, he would step in front of a train for her if he had to,” Westmoreland said. “I didn’t realize it might come to that for somebody else.”

The motive wasn’t immediately clear. Suspect Trystan Andrew Terrell had been enrolled at the school but withdrew during the current semester, UNC-Charlotte spokeswoman Buffy Stephens said. Campus Police Chief Jeff Baker said Terrell had not appeared on their radar as a potential threat.

“I just went into a classroom and shot the guys,” Terrell told reporters Tuesday as officers led him in handcuffs into a law enforcement building.

Terrell, 22, was charged with two counts of murder, four counts of attempted murder and other charges.

Putney said the suspect didn’t appear to target any particular person but did deliberately pick the building where it happened. He wouldn’t elaborate on why. Authorities said the anthropology class was fairly large, without being specific about how many students were present. Putney said the handgun used in the shooting was purchased legally.

Terrell is under observation in police custody, and his father and attorney haven’t been allowed to speak to him, his grandfather Paul Rold said today.

“His dad hasn’t a clue about what happened, or why it happened,” said Rold, of Arlington, Texas.

Terrell was on the autism spectrum but was “clever as can be” and bright enough to learn foreign languages, Rold said. He said his grandson wasn’t very social.

Rold said the Charlotte campus shooting is the latest in a long line of mass shootings that won’t end until laws reduce the volume of guns readily available.

“It’s unfortunate that in our society it can be so easily perpetrated. He has no background in guns or gun collecting, gun interest,” he said. “And how, in a short period of time, he was able to secure these weapons —legally, illegally, however— is the problem until Congress does something. If Sandy Hook, if Las Vegas, if Florida and these multiple incidents like yesterday can’t get them to move, if they’re more interested in reelection than the value of human life, this thing will continue.”

A campus vigil for the victims was planned for this evening. In a news release, UNC-Charlotte said all the victims were students, five from North Carolina and one international. Howell, of Waynesville, and Ellis R. Parlier, 19 of Midland, were killed in the attack. Those injured were Sean Dehart, 20, and Drew Pescaro, 19, both of Apex; Emily Houpt, 23, of Charlotte; and Rami Alramadhan, 20, of Saihat, Saudia Arabia.

After the shooting, students and faculty scrambled to find safe spaces on the campus of nearly 30,000 students, enduring a lengthy lockdown.

In a class a few rooms away from where the shooting happened, Krysta Dean was about to present a senior research project when she heard someone scream “shooter.” The anthropology major huddled behind a table with her classmates.

“The only thing that was going through my head was, one, I could very well die today. … I was mentally preparing myself for what it would be like to get shot and just kind of bracing myself for if it did happen,” she said.

Dean didn’t sleep much Tuesday night because she couldn’t get the noises out of her head. Now, she says she feels guilty for surviving.

“When I was sitting there on the floor, thinking that I might get a bullet in my head, my biggest fear was somebody’s reality. And there are parents that are never going to be able to hug their children again,” she said.