'Nightline' Daily Line, July 20: Mass Shooting in Colorado Theater

Overnight, ABC News learned of a mass shooting at a movie theater in Aurora, Colo., during "The Dark Knight Rises" midnight premiere. We will be posting links to our coverage here.

8:13 p.m. ET: Police tapes of the deadly shooting this morning in Aurora, Colo., reveal the unfolding crisis as law enforcement and emergency personnel responded to the worst mass shooting in U.S. history.

The first dispatch went out at 12:39 a.m., when 911 received calls that "somebody is shooting inside the auditorium" of a movie theater in Aurora.

Read the full story HERE

6:45 p.m. ET: "The movie theatre is my home, and the idea that someone would violate that innocent and hopeful place in such an unbearably savage way is devastating to me. Nothing any of us can say could ever adequately express our feelings for the innocent victims of this appalling crime, but our thoughts are with them and their families." - "Dark Knight Rises" director Christopher Nolan in response to the Colorado movie theater shooting.

Credit: ABC News

4:33 p.m. ET: ABC News complied advice from experts on how to talk to children of all ages about the Colorado movie theater shooting.

"Young children may have difficulties identifying and expressing feelings. Parents should pay attention to the children's play (for instance, preoccupation with certain aggressive electronic games, drawings, repetitive play that imitates the traumatic event or events). Another sign of trauma is avoidance of reminders (in this case, going to the movies or to a show or watching certain movies or avoiding other activities that they didn't avoid before)." - Dr. Aurelia Bizamcer, Medical Director, Outpatient Psychiatry at Temple University Hospital

Read the full story HERE

3:11 p.m. ET: First photos of shooter's mask and gear, posted by the Associated Press:

Credit: David Zalubowski/AP

Credit: David Zalubowski/AP

2:45 p.m. ET: Police scanner audio, 911 calls. Warning: disturbing content.

2:24 p.m. ET: White House announces that flags will be flown at half-staff at the White House, all public buildings and grounds, at all military posts and Naval stations, and on all naval vessels today.

2:01 p.m. ET: Updated casualties: 71 people shot, 12 dead, 59 injured. One moviegoer was injured when a bullet went through the wall and entered an adjoining theater.

1:21 p.m. ET: Suspected gunman's car had hundreds, if not over a thousand, rounds of ammunition.

12:55 p.m. ET: "We can come together and show our fellow citizens the good heart and love" - Mitt Romney comments on shooting.

12:22 p.m. ET: First confirmed photo of the shooter revealed. He was a PhD student who recently withdrew from his neuroscience studies at the University of Colorado before shooting up "The Dark Knight Rises" screening. LATEST

Credit: University of Colorado Denver/AP Photo

11:40 a.m. ET: Witness Jennifer Seeger was sitting in the front of the theater when a gunman entered and said he pointed "his gun in my face."

10:55 a.m. ET: Both the Obama and Romney campaigns cancel events and pull political attack ads in the wake of the shooting.

Read the latest HERE

10:51 a.m. ET: President Obama hosts a moment of silence to for victims of the shooting and other violent crimes.

10:45 a.m. ET: President Obama addresses the nation about the deadly Colorade movie theater shooting. WATCH LIVE: http:// abcn.ws/Hc36Zr

9:51 a.m. ET: VIDEO: Mother IDs Alleged Colorado Gunman With 'Gut' Instinct

9 :05 a.m. ET: President Obama will address the Colorado shootings at a previously-scheduled campaign event in Fort Myers, Fla. ABC News will carry a special report.

Read the president's statement on the shooting HERE

8:50 p.m. ET: A San Diego woman identifying herself as James Holmes's mother spoke briefly with ABC News this morning.

She had awoken unaware of the news of the shooting and had not been contacted by authorities. She immediately expressed concern that her son may have been involved.

"You have the right person," she said.

8:36 a.m. ET: More photos from the scene.

Credit: HO

and raw video:

8:00 a.m. ET: BREAKING: A lone gunman dressed in riot gear burst into a movie theater in Aurora, Colo., at a midnight showing of the Batman film "The Dark Knight Rises" and methodically began shooting patrons, killing at least 12 people and injuring at least 50.

Credit: Karl Gehring/Courtesy The Denver Post

"Good Morning America" devotes entire broadcast to continuous coverage of the shooting.