Students returned to classes at Arapahoe High School on Tuesday.
CENTENNIAL, Colo. - When an armed student went into Arapahoe High School on Dec. 13, many people sprung into action.
There was the janitor who initiated the school lockdown, the teachers who immediately locked their doors and hid their students, the students who ran to get help for shooting victim, Claire Davis, and the school resource officer and security guard who ran toward the gunman.
-- Custodian Fabian Llerenas --
Custodian Fabian Llerenas was one of the first people to see the gunman.
Llerenas told 7NEWS that he saw a student dressed in military or tactical gear running through the school. He thought the black object swinging on the gunman's arm was a guitar case.
"It just looked weird," Llerenas said. "He went in and that's when I heard two pops. That's when I knew. I said, 'They are shooting in the school.'"
Llerenas said he called for help.
Arapahoe County Sheriff Grayson Robinson praised Llerenas for starting the lockdown procedures.
He said the quickly-implemented lockdown protocol helped save lives.
Llerenas also saw the librarian who works as the school's speech and debate team coach leaving the school. The debate team coach was the staffer the gunman was targeting because he had been disciplined the student gunman, officials say. Llerenas took the speech and debate team coach with him to his truck outside the school.
Robinson praised the coach for leaving because Robinson felt the coach removed the threat from the school.
The gunman fired two shots in the library, one near the coach's office, and started a fire in the library before taking his own life.
-- Teachers --
Several students at Arapahoe High School told 7NEWS they heard a girl outside their class yelling "There's a shooter!"
Arapahoe High School student Courtney Leytoldt told 7NEWS when her teacher heard that, she put all the students in a closet to protect them.
Other students said their teachers enacted the active shooter protocol and locked doors and ushered students into rooms with locks.
-- Security guard, sheriff's deputy and assistant principal --
At Claire's memorial service on Wednesday, her father, Michael Davis, specifically thanked school resource officer, Deputy James Englert, and Rod Mauler, an unarmed school security guard and retired deputy, who both ran to the library after hearing the gunfire. He also thanked assistant principal Darrell Meredith who, along with Mauler, carried Claire to a safe area.
"Thank you to Deputy James Englert for not only fulfilling your duty with the utmost bravery but for following your heart that led you down an empty corridor to find Claire. Thank you Rod Mauler and Darrell Meredith who risked your lives by carrying Claire to safety while you were in an unsecured and dangerous area," the father said.
During a news conference this week, Sheriff Robinson also lauded the life-saving actions of Englert and Mauler. Englert reportedly ran from the cafeteria to the library, yelling for people to get down and identifying himself as a deputy sheriff.
"We are confident that the murderer knew they were in his immediate area," Robinson, Engler's boss, said.
"The officer went immediately to the threat, as he was trained," Robinson explained. "Try to go to the threat and eliminate the threat."
"James Englert is a hero, he saved lives," Robinson said.
"I am confident and believe strongly that the reason this incident took less than 1 minute and 20 seconds was the result of a very effective lockdown protocol that went into place immediately in collaboration with immediate and timely response by an armed school resource officer and an unarmed school security guard."
Mauler is a retired Arapahoe County sheriff's deputy. Mauler retired in 2009. He worked for the sheriff's office for 27 years.
Coverage: Arapahoe High School Shooting
Teachers and staff went back to work at Arapahoe High School on Monday. Students will return to classes on Tuesday.
An online petition drive is asking Littleton Public Schools to give Arapahoe High School shooting victim Claire Davis a diploma at graduation in May.
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