HIGHLANDS RANCH, Colo. — Emotions are running high as prosecutors prepare to bring charges against two teens accused of attacking their suburban Denver charter school earlier this week, killing one classmate and injuring eight others.

The pair are due in court Wednesday amid many questions about the shooting, how it was planned, and whether it could have been prevented.

Authorities say the student who died, Kendrick Castillo, saved lives as he and two other students rushed at least one of the shooters. A school security guard is credited by his boss with disarming and confronting the other shooter.

But aside from those details, many questions remain about the how and why of this attack, and investigators have persuaded a judge to temporarily keep most court records and reports secret.

Who are the suspects?

We know very little about the two suspects, in part because some media outlets have deliberately avoided reporting on them as part of the #NoNotoriety campaign. That campaign, organized by survivors of other mass shootings, asks the media to downplay coverage of accused shooters to avoid copycat incidents and to avoid “rewarding” shooters with attention.

The Douglas County Sheriff’s Office is withholding booking photos to avoid compromising the investigation.

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Authorities have identified the two suspects as Devon Erickson, 18, and a juvenile identified both as Maya McKinney and Alec McKinney. Appearing in court earlier this week, McKinney’s mother said he identifies as male and is known as Alec. Court records identify McKinney as Maya.

We don’t yet know the nature of the relationship between the two accused shooters.

Erickson’s social media accounts show he was interested in music and theater. In court Wednesday, he appeared shackled and in a red jail jumpsuit, with his purple-and-black dyed hair partially obscuring his face. Neither he nor McKinney spoke, aside from brief responses to the judge.

What was their motivation?

Unclear. While some mass shooters publicize their actions on social media or via a “manifesto,” the suspects in this case do not appear to have given any indication. Investigators have declined to discuss the case, and the judge has ordered all court filings temporarily sealed during the initial investigation.

In Colorado, prosecutors and defense attorneys are generally barred by professional ethics rules from discussing cases outside the courtroom. We should learn more about the case during Wednesday’s court hearing, where prosecutors are expected to file formal charges.

Parents of STEM students say they’re shocked at what happened, in large part because the school fosters and environment of personal accountability and acceptance. Candace Craig, who has three kids at the school, said she thinks understanding their motivation could help prevent future incidents.

“I want to call them names and reduce them to their actions, but when it’s this close to home, there’s a piece me that can’t reduce them to what they did,” she said. “We need to hear from them, but I don’t know how that looks in a healthy way.”

Could this have been prevented?

The STEM School did not have a metal detector at its doors, and it was patrolled by a contracted security guard. The security guard disarmed and detained one of the shooters, the guard’s boss said. But because the guard was in a different part of the school when the shooting began, he had to rush to the area.

Three students are credited with disarming the other shooter by wrestling the gun away. The sole death in the incident occurred when one of those students, Kendrick Castillo, was shot as he rushed the shooter.

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Thursday, it emerged that an anonymous woman claiming to be a STEM parent made serious accusations against school administrators late last year.

In a call to the school district where the STEM School operates, the woman described rampant bullying, drug use and her fears of a “a repeat of Columbine” at the semi-autonomous charter school. The anonymous complaints alarmed authorities enough that they requested an investigation by police and school officials.

It’s not yet clear whether there’s any connection between the woman’s complaints and the Tuesday attack. As a charter school, the STEM School is largely exempt from the rules and policies governing neighboring public schools, although it is still accountable to the district via a legal agreement.

STEM School officials in January adamantly rejected the woman’s concerns and sued her for defamation, according to court records and a letter sent by district officials to the school and obtained by USA TODAY. Because the woman’s call was made anonymously, STEM School officials asked a judge to subpoena phone records to find her.

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What about the actions of the private security guard?

Several media outlets have reported that investigators are looking into allegations that the school’s private security guard shot at either a student or a responding police officer during the incident. Authorities have declined to address that aspect of the case while the investigation is ongoing.

Security company founder Grant Whitus rejected the suggestion, saying his guard, a former sheriff’s deputy and U.S. Marine, is well trained. He said the guard was interviewed by detectives after the incident. Whitus, a former sheriff’s deputy, said the actions of the investigators indicate his guard acted appropriately.

“In my 27 years in law enforcement, if I believed somebody had shot someone in a school I would have never released them in an hour,” Whitus said. “That says something to me about this situation.”

What happens next?

The two suspects are due in court Wednesday. Prosecutors are expected to announce what charges the two will face. Part of that decision will include whether to prosecute McKinney as an adult or juvenile.

Colorado law permits prosecutors to file adult charges of serious felonies against 16- and 17-year-olds without prior approval from a judge.