The investigation into a mass shooting at the end of the Kansas City Chiefs’ Super Bowl parade and rally continued Thursday as details emerged about the role some of the Chiefs had in calming their community.One person was killed and 21 injured – seven critically — in the shooting near a parking garage west of Union Station, where an estimated 1 million people had gathered as players and team personnel took the stage to celebrate with fans.The wounded included nine children.Stacey Graves, the city’s police chief, said Wednesday night three people had been detained. At a news conference Thursday morning, officials reported that indications are the shooting was a result of an argument between people attending the parade that resulted in gunfire, but Graves declined to provide further details as the investigation continues.Earlier Thursday, speaking on “Good Morning America,” Chiefs offensive lineman Trey Smith recounted the horror and the role he and a teammate played in helping others.”I just remember the security guards ushering us through the doors quickly, saying, ‘Come on, hurry up, hurry up, hurry up,'” Smith, 24, said about how he learned of the active shooter. “‘This is not a joke. It’s a life and death situation.'”Smith said he and long snapper James Winchester found a closet to hide in along with 20 or so others, and he credited Winchester for calming others.Smith said he also encountered a young boy frightened after the joyous festivities turned terrifying.