Colorado school shooter is seen in court as his believed accomplice, 16, will ...

Two Denver high school students accused of fatally shooting a classmate and wounding eight others last week appeared in court on Wednesday to be formally charged with murder.

Colorado prosecutors have now charged both Devon Erickson, 18, and Alec McKinney, 16, with murder, attempted murder, and a series of other counts relating to the shooting at the STEM School Highlands Ranch on May 7.

McKinney, who was listed on the court docket by the name Maya Elizabeth McKinney but identifies as male, will also be tried as an adult, the court confirmed.

Erickson and McKinney were arrested at the high school after investigators say they opened fire on their fellow students in two different classrooms using handguns that had been concealed in a guitar case.

Devon Erickson (pictured), 18, and Alec McKinney, 16, have been charged with murder, attempted murder, and a other counts relating to the shooting at STEM

Unlike his court appearance last week, Erickson appeared more involved and engaged during Wednesday morning’s proceedings

Unlike his court appearance last week, Erickson appeared more involved and engaged during Wednesday morning’s proceedings

The two teens made their initial court appearances last week in separate hearings before Douglas County District Judge Theresa Slade, who ordered them both held without bond.

Denver's ABC affiliate television station has reported that the two pistols used in the attack were stolen from the home of Erickson, whose parents had purchased the guns legally.

Unlike his court appearance last week, Erickson appeared more involved and engaged during Wednesday morning’s proceedings.

Instead of looking down at his feet with his face concealed by his pink and black dyed hair as he had before, Erickson’s face was visible while he looked forward to address the judge directly.

Wearing a prison uniform, Erickson was shackled by his wrists and ankles throughout the hearing, as Judge Theresa Slade denied a motion to have them removed.

Alongside his charges of murder and several counts of attempted murder, Erickson is also facing charges of theft and arson in relation to the attack.

Court documents in the case remain sealed. Slade denied the prosecution's request to make some of the documents public but said she will address the issue at the next hearing on June 7.

Instead of looking down to his feet with his face concealed by his pink and black dyed hair as he had before, Erickson’s face was visible while he looked forward to address the judge directly

Instead of looking down to his feet with his face concealed by his pink and black dyed hair as he had before, Erickson’s face was visible while he looked forward to address the judge directly

Wearing a prison uniform, Erickson was shackled by his wrists and ankles throughout the hearing, as Judge Theresa Slade denied a motion to have them removed

Wearing a prison uniform, Erickson was shackled by his wrists and ankles throughout the hearing, as Judge Theresa Slade denied a motion to have them removed

Alec McKinney, 16, who was listed on the court docket by the name Maya Elizabeth McKinney but identifies as male, will also be tried as an adult, the court confirmed

Alec McKinney, 16, who was listed on the court docket by the name Maya Elizabeth McKinney but identifies as male, will also be tried as an adult, the court confirmed

Joshua Jones, an 18-year-old senior at STEM School Highlands Ranch, said during a news conference Tuesday he was watching The Princess Bride in his British literature class when a classmate pulled a gun and told everyone to stay still.

Jones said he was acting on instinct when he, Kendrick Castillo and Brendan Bialy subdued one of two students who attacked the south Denver school.

We rushed him. I pulled him to the ground, Kendrick got the gun out of him, I shoved him to the wall,' Jones explained.

He was shot twice in one leg but said he is recovering quickly.

'There wasn't a whole lot that was

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