One person was killed and three other people were shot Thursday when a gunman with a shotgun entered a building on the campus of Seattle Pacific University and opened fire, police said. When the gunman began reloading, a student who is a building monitor subdued the shooter with pepper spray, according to Capt. Chris Fowler of the Seattle Police Department. Other students then joined the monitor and held the shooter down, he said. 'They were able to pin the shooter to the ground until police arrived,' Fowler said during a news conference. The gunman was taken into custody a short time after. The victims were taken to the hospital with gunshot wounds that ranged 'from minor to life threatening,' the Seattle Fire Department said. One of the victims, a 20-year-old man, was pronounced dead at Harborview Medical Center, according to police. Another victim, a woman, has life-threatening injuries. The other two victims, a man and a woman, are both in stable condition. 'This is a tragic moment for Seattle and a tragic moment for America once again,' Seattle Mayor Ed Murray (D) said in a news conference. This shooting occurred shortly before 3:30 p.m. in Otto Miller Hall, a science and engineering building on the campus of Seattle Pacific. The small school, located about 10 minutes away from downtown Seattle, remained locked down for about 90 minutes after the shooting. Police declared Otto Miller Hall secure at around 5 p.m. and the lockdown ended shortly after that. All evening classes were canceled.