Based on Loughner's often-incoherent ramblings on social media Web sites, it seems the four heroes stopped him from ending the massacre by offing himself.
"Goodbye, friends," Loughner posted on his now-deleted MySpace page before the incident.
Dylan Kleibold and Eric Harris, the gunmen who orchestrated the shooting massacre at Columbine High School in 1999, ended their own lives after they had carried out their plans.
Other indications that Loughner planned to kill himself after carrying out the attack come from a collection of bizarre notes found in a safe at his home.
On one of the notes, Loughner apparently scrawled "Giffords." On another, he wrote "my assassination." On the third, Loughner wrote "I planned ahead" -- as if to offer some type of explanation to those investigating the shooting after presuming he wouldn't make it out of
the attack alive.
Loughner's apparent suicidal plan was cut short by the heroic efforts of four people, one who prevented him from reloading his Glock 9-millimeter after unloading his first ammo clip into the crowd, and three others who restrained him until police arrived.
According to the Pima County Sheriff's Office's account of what went on after Loughner shot Giffords and 18 others, Patricia Maisch, who was waiting in line to take a picture with Giffords when Loughner opened fire, grabbed the bottom of a fresh clip Loughner was trying to insert into his gun.
As Maisch and Loughner fought over the clip, two men, Roger Salzgeber and Bill Badger, tackled and restrained the suspect, while Joseph Zamudio held his legs until police arrived.
Loughner is expected to make his initial court appearance this afternoon. So far, he's been charged by the federal government with two counts of murder and three counts of attempted murder. If convicted, he could face the death penalty.
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