Raleigh, N.C. — Those who had catching a movie among their weekend plans may be having second thoughts after a lone gunman opened fire overnight in a Colorado theater, killing a dozen people and injuring dozens more.

Police in Aurora, Colo., say James Holmes, 24, entered a midnight showing of the Batman movie "The Dark Knight Rises," in tactical armor and made his way up the aisle, firing as he went, saying nothing. Police, ambulances and emergency crews swarmed on the scene after frantic calls started flooding the 911 switchboard, officials said.

By mid-day, the FBI was questioning Holmes, who told them he had a cache of booby-trapped explosives in his apartment.

While some theaters and police around the U.S. stepped up security at daytime showings of "The Dark Knight Rises," most Triangle-area communities were not planning any additional law enforcement presence.

Theaters in Cary and Fayetteville hire off-duty officers for security, officials with those towns said. Neither police department had plans to add to that number Friday.

Capt. Patrick Niemann, of the Raleigh Police Department's Southwest District, said all officers with theaters and other high-density areas on their regular patrols would be extra vigilant this weekend.

"Our patrol officers and our patrol element are obviously very cognizant of the events in Colorado, and we will increase patrol around the more densely populated areas however, the specific security within the theaters – that's up to the individual establishment," he said.

All Raleigh police officers are trained in "active shooter" situations to first stop the threat," Niemann said, including going inside a building to get to and stop a shooter.

"We train frequently. We have state-mandated training, but on top of that, we pride ourselves with infusing our training curriculum with significantly more than what the state requires," he said. "We do prepare for tragic incidents such as Aurora."

Big cities bulk up police presence

The New York City Police Department was posting officers at about 40 theaters around the city that were showing the film. The increased security was a precaution against potential copycat shooters, and also meant to reassure moviegoers.

In Washington, the Homeland Security Department held a conference call with officials from the commercial, entertainment and shopping mall industries to discuss what security measures they could take to prevent something like this from happening again.

At the Regal Gallery Place multiplex in downtown Washington, moviegoers trickled into an 11 a.m. showing. Theater employees searched patrons' bags and purses while taking their tickets.

The National Association of Theater Owners said in a statement that its members are "working closely with local law enforcement agencies and reviewing security procedures." AMC Theaters said it is "actively working with local law enforcement in communities throughout the nation and under the circumstances, we are reaching out to all of our theaters to review our safety and security procedures."