Multiple students were wounded, including one fatally, in a shooting at Seattle Pacific University on Thursday afternoon.
At least three people were shot in the school's science and engineering building, according to the Seattle Police Department.
One man who was taken to Harborview hospital later died, the Associated Press reported.
Officials at the hospital told KIRO-TV that a 20-year-old woman with life-threatening injuries was undergoing surgery. A 24-year-old man and a 22-year-old man are in satisfactory condition. According to the Associated Press, one of those men was not shot.
The gunman, who opened fire in a building foyer around 3:30 p.m. armed with a shotgun and knife, was disarmed by a student building monitor when he tried reloading, Seattle PD Capt. Chris Fowler said at an evening press conference. As the suspect was subdued, other students piled on to help. Pepper spray was used to subdue the suspect, Fowler said.
Suspected gunman Aaron R. Ybarra, 26, was booked into King County Jail, the Seattle Police Department announced early Friday morning. Authorities say he is not believed to be a student at the school.
The university announced via Twitter that the shooting took place near Otto Miller Hall. SWAT officers checked additional SPU buildings around the private college after capturing the suspect, police said.
One physics student told a Seattle Times reporter that he walked through "pools of blood" when police evacuated his building.
The waterfront Christian university has about 4,000 students and is 10 minutes from downtown Seattle, according to the Associated Press.
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SEATTLE (AP) — When a lone gunman armed with a shotgun at a small Seattle university stopped firing at students to reload, another student pepper-sprayed him and subdued him with the help of others and prevented more deaths, police said.
"There are a number of heroes in this," Assistant Police Chief Paul McDonagh said. "The people around him (the gunman) stepped up."
A 19-year-old man was fatally shot and two other young people were wounded after the gunman entered the foyer at Otto Miller Hall on the Seattle Pacific University campus and started shooting Thursday afternoon. When he paused to reload, a student building monitor disarmed him. The gunman had additional rounds and a knife, McDonagh said.
"But for the great response by the people of Seattle Pacific, this incident might have been much more tragic," he said.
The man in custody was not a student at the school, McDonagh told a news conference.
Four people, including the young man who died, were rushed to Harborview Medical Center. A critically wounded 20-year-old woman was in intensive care late Thursday night after about five hours in surgery, hospital spokeswoman Susan Gregg said. A 24-year-old man was hospitalized in satisfactory condition. A Seattle Fire Department official said the man suffered "pellet type wounds" to his neck and chest.
A 22-year-old man was treated and released, Gregg said. Police said he suffered minor injuries during the struggle with the suspect.
None of the victims was immediately identified.
Aaron R. Ybarra, 26, was booked into the King County Jail late Thursday for investigation of homicide, according to police and the jail roster.
Also late Thursday, police who said they were serving a warrant entered a house that was believed tied to Ybarra. A phone message left at that house in the north Seattle suburb of Mountlake Terrace was not immediately returned.
Messages left with friends and relatives of Ybarra via social media were not immediately returned.
Student Chris Howard was at Otto Miller Hall when the shooting happened. He said he saw the wounded young woman on the floor being tended to by a classmate. Her chest was bloodied. Her phone was covered in blood, but she asked her helpers 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.'"
Soon after, police arrived. By then the suspect had been subdued. Howard ran outside and back through the lobby where he saw the man pinned on the floor.
"The suspect was calm. Not speaking. Not moving. Not struggling. Just there," Howard said.
The afternoon shooting came a week before the end of the school year, and the situation was particularly tense when police initially reported that they were searching for a second suspect.
"It appears the suspect acted alone," McDonagh said.
He said he did not know the gunman's motive or intended target. Detectives are "working as quickly as we can to figure it out," McDonagh said.
The university locked down its campus for several hours, and it alerted students and staff to stay inside. Some students were taking finals in the same building that the shooter entered.
Both the young man who died and the young woman suffered gunshot wounds to the body, Seattle Fire Assistant Chief Jay Hagen told the news conference.
On Thursday evening, people packed the First Free Methodist Church on campus for a service of prayers and song. So many people crowded into the building that dozens of people gathered on a lawn near the church and formed their own groups as the sun set.
"We're a community that relies on Jesus Christ for strength, and we'll need that at this point in time," said Daniel Martin, university president.
About 4,270 undergraduate and graduate students attend the private Christian university. Its 40-acre campus is in a leafy residential neighborhood about 10 minutes from downtown Seattle. The school canceled classes and other activities Friday.
Jillian Smith was taking a math test on the second floor of Otto Miller Hall when a lockdown was ordered.
She heard police yelling and banging on doors in the hallway. The professor locked the classroom door, and the 20 or so students sat on the ground, lining up at the front of the classroom.
"We were pretty much freaking out," said Smith, 20, a sophomore. "People were texting family and friends, making sure everyone was OK."
About 45 minutes later, police came and escorted them out of the building two by two, she said. On the way, they passed the lobby where she saw bullet casings and what appeared to be blood on the lobby carpet and splatter on the wall.
"Seeing blood made it real," Smith said. "I didn't think something like this would happen at our school."
The gun violence follows a spate of recent shootings on or near college campuses.
Last month, according to police, Elliot Rodger killed six people and injured seven before turning his gun on himself in a rampage in Isla Vista, California, near two universities.
Seven people were killed and three injured when a 43-year-old former student opened fire at a tiny Christian school, Oikos University, in Oakland, California, in 2012. A gunman killed five people and injured 18 when he opened fire in a Northern Illinois University lecture hall in 2008.
In 2007, 32 people were fatally shot in a dorm and classroom at Virginia Tech in Blacksburg, Virginia, before the gunman killed himself.
Seattle Mayor Ed Murray, noting previous mass shootings in the city, said: "Once again the epidemic of gun violence has come to Seattle."
AP reporters Donna Gordon Blankinship in Seattle and Rachel La Corte in Olympia, Washington, contributed to this report.