The shooting unfolded early Friday morning inside a darkened theater in Aurora, Colorado, packed with Batman fans, some in costume for the movie's premiere.
Twelve people were killed and 59 were wounded in the attack, according to police in Aurora.
The suspected gunman, identified as 24-year-old James Holmes was arrested in a rear parking lot of the theater.
The tragedy has prompted Warner Bros., the studio behind the movie, to cancel the film's Paris premiere, which was scheduled for Friday night.
Director Christopher Nolan, as well as stars Christian Bale, Anne Hathaway and Morgan Freeman were expected to attend.
"Warner Bros. is deeply saddened to learn about this shocking incident," the studio said in a statement on Friday. "We extend our sincere sympathies to the families and loved ones of the victims at this tragic time."
Warner Bros. has reportedly canceled all media interviews and promotional appearances with the cast ahead of the movie's much-anticipated opening weekend.
Box office analysts have predicted that it would rake in between $175 million and $195 million in its opening weekend -- the best U.S. opening ever for a non-3D movie.
It took in $30.6 million in midnight screenings Friday night at 3,825 locations, surpassing the benchmark set by "The Avengers" in May on its way to the biggest opening weekend ever at $206.4 million.
The movie is set to be seen in a total of 4,404 theaters, with a record 332 IMAX venues.
The film will also roll out on 6,765 screens overseas in 17 territories.
Warner Bros. was still deciding whether to take further measures, including canceling screenings at theater chains, according to TheWrap.
One executive told TheWrap that the studio would be making decisions on Friday and throughout the weekend as they monitored news reports and spoke to theater chains.
A spokesman for the Knoxville, Tenn.-based Regal theater chain told TheWrap, "We will continue to monitor the situation and adjust our security needs as necessary."
The Los Angeles County Sheriff's Department says it is on "heightened alert" after the shootings. It will increase patrols and maintain a more visible presence at theaters.
In New York City, police are also increasing their patrols at theaters playing "The Dark Knight Rises," according to police commissioner Ray Kelly.
Kelly said the increased police presence is "a precaution against copycats and to raise the comfort levels among movie patrons in the wake of the horrendous shooting in Colorado."
Meantime, a source close to Warner Bros. told the Los Angeles Times that the studio has pulled trailers for its upcoming film "Gangster Squad" from all theaters.
The movie centers on the Los Angeles Police Department's secret 1940s anti-mob gangster squad.
In one of it's key scenes, mobsters go backstage at Grauman's Chinese Theater in Hollywood and open fire through the screen at the audience.
The movie is set for release Sept. 7, and trailers for the film -- including snippets of the movie theater scene -- have already been playing.
The trailer did not play before the screening in Aurora, the source told the Times.
It remains to be scene whether the studio will take steps to shorten or remove the scene from the film itself.