Cinemark is banning all large bags from their theaters across the nation in an effort to enhance the "safety and security" of moviegoers.

In a post on its website, Cinemark explained the new policy saying any bags measuring larger than 12" x 12" x 6" were banned from their theaters. Exceptions will be made for those people with medical equipment bags and "diaper bags." 

The theater chain warned patrons who go to the theater with large bag will be asked to place them back in their car as there is no storage available in their theaters.

In August 2012, a mass shooting occurred inside a Century 16 movie theater in Aurora, Colorado during a midnight screening of the film The Dark Knight Rises. A gunman, James Holmes, set off tear gas grenades and shot into the audience with multiple firearms, killing twelve people, and wounding 70 others. The gunman, James Eagan Holmes was arrested outside the cinema only a few moments later. 

Cinemark operates more than 530 theaters with almost 6,000 screens in the U.S.. They are the third-largest theater chain, behind AMC and Regal Entertainment.