SEATTLE — A campus shooting that killed one and injured three others would have been more dire if another student had not acted quickly, said a professor who witnessed the violence.

Associate Professor Kevin Bolding, chairman of the Electrical Engineering Department at Seattle Pacific University, said he heard gunshots about 3:30 p.m. PT Thursday as he sat in his office, so he picked up his phone and called 911.

"I heard a shot outside my window and saw a may laying on the ground and a person holding a gun over him," said Bolding, who then heard another shot inside the building. "And I looked down from my office and saw one of my students sitting on top of somebody, and a big pile of shell casings. As far as I know, he tackled the shooter, took him out and saved us all."

A student building monitor at Otto Miller Hall on campus first confronted the shooter, identified as Aaron R. Ybarra, 26, Seattle Police said. Ybarra was booked into King County Jail late Thursday for investigation of homicide.


1 dead, 3 hurt in shooting at Seattle Pacific University

On Friday, university spokesmen officially identified the building monitor who pepper-sprayed and helped subdue the suspect as engineering student Jon Meis, 22. On Twitter, many Seattle Pacific students already were calling him a hero.

"If he hadn't done that, we would've been in much bigger trouble," Bolding said.

Meis has been a student security monitor and teaching assistant at the university, a 4,300-student private Christian school north of downtown, since January 2012, according to his LinkedIn profile. He has been an intern at Boeing since June 2013.

The student was among those transported to Seattle's Harborview Medical Center. A spokeswoman there said Friday that Meis wasn't injured but was suffering from mental anguish. He was treated and released Thursday.

Bolding was visibly shaken as he left the building, as were many of the students and staff that were on lockdown during the shooting and the investigation that followed.

"It's supposed to be a safe place," Bolding said. "I can't believe it happened here." None of the victims was identified as of Friday.

Student Chris Howard helped two students who were injured.

"I was working on a project in machine shop after I was done with classes for the day. I'm just dremeling and doing stuff that you do in the machine shop and one of my friends from thermodynamics class rushes in — obviously frantic and looking behind him — and first thing he says is, 'Close the door behind me. Are the other doors locked?' " Howard said.

"One person runs to the garage door and closes it, and we start ripping the first aid kit off of the wall because he had a couple of marks on his neck that were bleeding. We didn't know what happened. First we thought, goose attack, it came from the canal," Howard said. "It obviously wasn't a goose."

Howard and others in the room put gauze on the victim's neck as he mentions he was shot. Then Howard goes to find additional medical help.

"(In) the hallway in the part of the machine shop, I see another student kneeling over someone that's lying down," he said. "I see the person who's lying down, their chest is red and appears to have a tourniquet around their arm. I basically get instructed to have her head on my lap."

Her phone was covered in blood, but she asked those helping her to look through her phone for her mother, aunt and best friend.

"She was panicking," Howard said. "She said 'I think I'm going to die.' "

A 19-year-old woman was critically wounded, said officials Friday at Harborview Medical Center, where she had surgery. A 24-year-old man is in satisfactory condition with pellet fragment wounds to his neck and chin and could be released Saturday.

A 19-year-old man died Thursday after arriving at the hospital.

If he hadn't done that, we would've been in much bigger trouble.

Kevin Bolding, Seattle Pacific University

At least three fatal shootings have taken place on college campuses across the USA since the beginning of the year: In January, teaching assistant killed a fellow TA at Purdue University in West Lafayette, Ind. Later that month, a student killed another student at South Carolina State University in Orangeburg, S.C. In March, police officers at Columbus State University in Georgia killed a man seen loading a gun near on-campus apartments.

Other universities have been put in lockdown as shooters wounded students who survived. Still other shootings, including a May 23 rampage that killed six in Isla Vista, Calif., have taken place near campuses.

Friday was to have been the final day of classes for the spring quarter at Seattle Pacific University. They were canceled, but faculty was asked to come to campus to be available to students.

A prayer service is at noon PT at First Free Methodist Church on campus. Final exams are next week.

Contributing: The Associated Press