Early Friday morning, 12 people died and dozens more were injured in a massive shooting at a midnight showing of "The Dark Knight Rises" in Aurora, Colo., and now the nation's theaters are on high alert. The New York City Police Department, for one, has already stepped up security in the wake of the mass shooting. European theaters are following suit.Special Section: Colorado movie theater massacre
Pictures: "The Dark Knight Rises" New York premiere
Pictures: "The Dark Knight Rises"
Pictures: Colo. police: 12 dead at theater shooting
"This is a tragedy, one that will no doubt send dark ripples down the aisles of every movie theatre from coast to coast," Jeff Bock, senior box office analyst at Exhibitor Relations Co., told CBSNews.com.
On a financial note, insiders say the massacre could hurt this weekend's movie box office earnings. Prior to Thursday's shooting, analysts predicted that "The Dark Knight Rises" could bring in $175 million through Sunday, reports Variety. That would make it the second-highest U.S. opening of all time -- behind only "The Avengers," which debuted with $207 million in May.
"Sadly, because of this event, a dark cloud will hang over 'The Dark Knight Rises' this weekend, which certainly may affect box-office grosses," Bock said. "Theatrical exhibition has never witnessed a tragedy like this inside a movie theatre, so it is extremely difficult to gauge the ramifications of this nightmare scenario."
Bock points out, though, that even discussing box-office numbers seems "trite when we're talking about the loss of lives."
When families head to the movies this weekend, things could feel different.
"One thing is for certain -- families will be much more cautious about bringing their brood to the theaters this weekend," Bock said.
"The Dark Knight Rises," with its estimated $250 million budget, was one of the most highly-anticipated films of the year, generating Oscar buzz eve before it opened. . Starring Christian Bale, Anne Hathaway and Michael Caine, the movie marks the final chapter in Christopher Nolan's dark Batman trilogy.