Deadly movie theater rampage in Aurora, Colo.
James Holmes was convicted on first-degree murder charges July 16, 2015 for killing 12 people and wounding dozens of others when he opened fire on July 20, 2012 during a midnight showing of "The Dark Knight Rises" at a movie theater in Aurora, Colo.
Aurora police said witnesses reported the shooter was wearing a gas mask and released some type of a canister. Witnesses said they heard a hissing sound and saw a gas - and then the gunman started shooting. Officers found Holmes near a car behind the theater and also located a gas mask, rifle, handgun and at least another weapon.
Holmes is seen here in a photo provided by the University of Colorado Denver.
Police respond
Police are seen outside a Century 16 movie theater where 12 people were killed and dozens more injured in a shooting during a midnight showing of "The Dark Knight Rises," in Aurora, Colo., July 20, 2012.
Obama calls Aurora mayor
Investigating the crime scene
An Aurora police officer talks on his radio outside of the Century 16 theater at Aurora Mall after the deadly movie theater shooting, in Aurora, Colo., July 20, 2012.
Police chief speaks to press
Aurora Police Chief Daniel Oates talks to media at Aurora Mall after the deadly shooting during a midnight screening of "The Dark Knight Rises" in Aurora, Colo., July 20, 2012.
Police respond
Police are pictured outside of a Century 16 movie theater at Aurora Mall after the deadly shooting during a midnight screening of "The Dark Knight Rises" in Aurora, Colo., July 20, 2012.
Police at the shooter's home
Police gather near an apartment house where shooter James Holmes lived, in Aurora, Colo., July 20, 2012.
Holmes was convicted of first-degree murder charges on July 16, 2015 for killing 12 people and wounding dozens of others.
SWAT at shooter's home
A SWAT team officer stands near an apartment house where "Dark Knight Rises" theater shooter James Holmes lived, in Aurora, Colo., July 20, 2012.
Holmes was later convicted of first-degree murder charges in 2015 for killing 12 people and wounding dozens of others.
The crime scene
Police are pictured outside of a Century 16 movie theater at Aurora Mall after a deadly shooting during a midnight screening of "The Dark Knight Rises" in Aurora, Colo., July 20, 2012.
A community mourns
A woman is pictured outside of a Century 16 movie theater after the deadly shooting during a midnight screening of "The Dark Knight Rises" in Aurora, Colo., July 20, 2012.
Police at the theater
Police are pictured outside of a Century 16 movie theater at the Aurora Mall after a deadly shooting during a midnight screening of "The Dark Knight Rises" in Aurora, Colo., July 20, 2012.
Moviegoers gather outside theater
Moviegoers are pictured with police outside of a Century 16 movie theater at the Aurora Mall after a deadly shooting during a midnight screening of "The Dark Knight Rises," in Aurora, Colo. on July 20, 2012.
Survivors gather
Family and friends wait outside Gateway High School where witnesses were brought for questioning after the deadly shooting at a movie theater "The Dark Knight Rises" on July 20, 2012 in Aurora, Colo.
Witnesses questioned
Survivors embrace
Emma Goos, 19, hugs her mother, Judy Goos, outside Gateway High School where witnesses were brought for questioning, July 20, 2012, in Aurora, Colo. Emma was in the third row of the theater of the Batman movie when the shooter entered. She helped apply pressure to a man's head who was injured.
Survivors embrace
Jacob Stevens, 18, hugs his mother Tammi Stevens after being interviewed by police outside Gateway High School where witnesses were brought for questioning after a shooting at a movie theater, July 20, 2012 in Denver.
Survivors embrace
Shamecca Davis hugs her son Isaiah Bow, who was an eyewitness to the shooting, outside Gateway High School where witness were brought for questioning, July 20, 2012 in Denver. After leaving the theater Bow went back in to find his girlfriend. "I didn't want to leave her in there. But she's ok now," Bow said.
Survivors embrace
A prayer for the victims
A small group prays outside Gateway High School where witness were brought for questioning, July 20, 2012 in Aurora, Colo. after the deadly movie theater shooting.
Police at the shooter's home
Police climb up a ladder to the window of the apartment of James Holmes on July 20, 2012 in Aurora, Colo.
In 2015, Holmes was convicted on first-degree murder charges for killing 12 people and wounding dozens of others.
Police at the shooter's home
Police at the shooter's home
Police use a video camera to look inside an apartment where the shooter lived in Aurora, Colo., July 20, 2012.
James Holmes was convicted on first-degree murder charges July 16, 2015 for killing 12 people and wounding dozens of others when he opened fire in a movie theater in 2012.
Searching the shooter's car
Police are pictured searching James Holmes' car parked outside the Century 16 movie movie theater at the Aurora Mall after the deadly shooting during a midnight screening "The Dark Knight Rises" in Aurora, Colo., July 20, 2012.
Holmes was convicted on July 16, 2015 of first-degree murder charges for killing 12 people and wounding dozens of others.
Searching the shooter's car
Police are pictured searching James Holmes' car parked outside the Century 16 movie movie theater at the Aurora Mall after the deadly shooting during a midnight screening "The Dark Knight Rises" in Aurora, Colo., July 20, 2012.
Holmes was convicted on July 16, 2015 of first-degree murder charges for killing 12 people and wounding dozens of others.
Police at the shooter's home
Police go through the trash near the apartment of James Holmes, the shooter who opened fire in a movie theater on July 20, 2012 in Aurora, Colo.
Holmes was convicted on July 16, 2015 of first-degree murder charges for killing 12 people and wounding dozens of others.
Century 16 Movie Theater
The Century 16 movie theater is seen where a gunman attacked movie goers during an early morning screening of "The Dark Knight Rises" on July 20, 2012 in Aurora, Colo.
Searching for loved ones
Tom Sullivan, center, embraces family members outside Gateway High School where he had been searching frantically for his son Alex Sullivan who celebrated his 27th birthday by going to see "The Dark Knight Rises," where James Holmes opened fire, July 20, 2012, in Aurora, Colo. Alex was later confirmed to be among the victims killed.
Searching for loved ones
Tom Sullivan, holds a photograph of his son, Alex Sullivan, as he pleads with the media to help him find his son, outside Gateway High School on July 20, 2012 in Aurora, Colo. Alex was later confirmed dead in the fatal movie theater shooting.
Searching for loved ones
A woman cries outside Gateway High School where witnesses were brought for questioning after a gunman opened fire at a midnight premiere of "The Dark Knight Rises," July 20, 2012 in Aurora, Colo.
Survivors interviewed
People are interviewed at the Century 16 movie theater where a gunman attacked movie goers during an early morning screening of "The Dark Knight Rises" July 20, 2012 in Aurora, Colo.
Police at the theater
Police pictured on the scene at the Century 16 movie theater where a gunman attacked movie goers during an early morning screening of "The Dark Knight Rises" on July 20, 2012 in Aurora, Colo.
Investigating the crime scene
Investigators pictured the scene at the Century 16 movie theater where a gunman attacked movie goers during an early morning screening of "The Dark Knight Rises" July 20, 2012 in Aurora, Colo.
A moment of silence
Colorado Rockies' Jason Giambi, center, looks out to the field as players observe a moment of silence for the victims of the Colorado theater shooting before the start of a baseball game against the San Diego Padres Friday, July 20, 2012, in San Diego.
The gunman, James Holmes, used a military-style semi-automatic rifle, a shotgun and a pistol, stopping only to reload. 12 people were killed and several dozens wounded in one of the deadliest mass shootings in recent U.S. history.
Holmes was later convicted on first-degree murder charges July 16, 2015.