LITTLETON, Colo. — The math teacher who has become a national hero after breaking up a potentially deadly school shooting near the site of the Columbine massacre said Wednesday that he was simply doing his job to protect his students from danger during his now-famous scuffle with the gunman.

Schools in Littleton have gone through extensive emergency drills after the Columbine tragedy, and David Benke said he always thought about what he'd do if a school shooting broke out.

"If something happens and there's something that I can do about it, I want to try and do something about it," Benke said at a news conference with other staff members from Deer Creek Middle School, at times choking up with emotion. "I said, 'I hope that I'm capable of doing something about it.'"

School officials praised the quick actions by Benke and his colleagues as further proof that preparations put in place after Columbine have paid off. But authorities are still investigating to better understand what happened, including why and for how long the gunman, 32-year-old Bruco Strong Eagle Eastwood, was inside the school building before the shooting.

Assistant principal Becky Brown said the suspect had signed in at the main office about noon Tuesday — some three hours before the shooting. Investigators were interviewing school staff members in attempt to reconstruct the day's events, and they have found live rounds from the hunting rifle at several places on school grounds.

Eastwood said nothing during a brief hearing Wednesday in which a judge set bail at $1 million cash. The unemployed ranch hand appeared by video hookup from the jail, wearing an orange inmate jumpsuit with his dark, shoulder-length hair hanging loose. He faces two counts of attempted first-degree murder.

Eastwood has an arrest record in Colorado dating back to 1996 for menacing, assault, domestic violence and driving under the influence, and he is believed to have a history of mental issues. The sheriff's department said Eastwood is a former student of the school who has been attending community college off and on in pursuit of his GED.

Authorities said he opened fire in the parking lot with the bolt-action rifle at the end of the school day as terrified teenagers ran for their lives. He had allegedly just wounded two students and seemed ready to unleash more violence when Benke sprung into action.

Benke confronted the gunman, tackled him and pinned him to the ground with the help of another teacher, stopping what could have been a much more violent encounter in a city all too familiar with tragic school shootings. The shooting occurred less than three miles from where the Columbine High School massacre happened nearly 11 years ago.

"Unfortunately he got another round off before I could grab him," Benke said. "He figured out that he wasn't going to be able to get another round chambered before I got to him so he dropped the gun and then we were kind of struggling around trying to get him subdued."

The two students survived Tuesday's shooting and one remained hospitalized. The student in the hospital is one of Benke's students, and the principal said he is "progressing well."

Meanwhile, Benke became a hero. A Facebook page called "Dr. David Benke Is A Hero!!!!" quickly grew to more than 17,000 members, and his actions were discussed on the floor of the state Senate.

"Sometimes that's just what we need. We need someone to be a hero for us," said state Sen. Mike Kopp of Littleton, who lives in Benke's neighborhood.

Benke, a father of 7-year-old twins and a 13-year-old girl, fought back tears after Jefferson County Sheriff Ted Mink thanked him Tuesday.

"Believe me when I say, I think he stopped what could have been a more tragic event than it was this afternoon," Mink said.

The victims, students Reagan Webber and Matt Thieu, were both treated at Littleton Adventist Hospital, where spokeswoman Christine Alexander said Webber was treated and released to her home.

Benke, a 6-foot-5 former college basketball player who oversees the school's track team, was monitoring the parking lot in the afternoon when he heard what he thought was a firecracker and began walking toward the noise.

"At first when I was walking over there, it was kind of what a teacher does," Benke said, still shaken hours after the shooting. "'Hey kid, what are you doing,' you know that kind of thing."

"I grabbed him from the front and we were dancing around pushing and shoving," he said.

In 2005, Eastwood participated in a NASA-funded medical study in which he spent 10 days in a hospital bed so scientists could study muscle wasting, an affliction experienced by astronauts during long flights, according to a story in the Rocky Mountain News at the time.

He told the newspaper that he had a lifelong dream of being an astronaut and described his occupation to the newspaper as horse trainer working at his father's ranch. He pocketed $2,200 from the study and was able to spend a week and a half watching DVDs and playing video games during the bed experiment.

A man who answered the phone Tuesday night at a number listed for Eastwood identified himself only as "Mr. Eastwood" and said he was Bruco Eastwood's father. He was at a loss for words.

"There's nothing you can say about it. What can you say?" the man told The Associated Press. "Pretty dumb thing to do. I feel bad for the people involved." He wouldn't comment further.

As for Benke, he said he still wishes he could have done: "It bugs me that he got another round off" before Benke tackled him to the ground.

Associated Press writers Samantha Abernethy in Littleton and Ivan Moreno and Thomas Peipert in Denver contributed to this story.