Photo Gallery: Colorado theater shooting 20/42

Tom Sullivan, center, stands with family members outside Gateway High School where witness were brought for questioning after a gunman opened fire at the midnight premiere of The Dark Knight Rises Batman movie Friday, July 20, 2012 in Aurora, Colo. Sullivan later pleaded with the media to help find his missing son, Alex Sullivan, who attended the movie to celebrate his 27th birthday.   A gunman wearing a gas mask set off an unknown gas and fired into the crowded movie theater killing 12 people and injuring at least 50 others, authorities said. (AP Photo/Barry Gutierrez) ORG XMIT: COBG116