WASHINGTON (CBSDC/AP) — The FBI and Homeland Security Department have advised law-enforcement officials around the country they’ve uncovered no information to indicate that more shooting sprees were being plotted for movie theaters around the country.

According to an intelligence bulletin obtained Saturday by The Associated Press, investigators had not figured out the suspected shooter’s motivations for killing 12 people and injuring dozens of others during a midnight showing of the new Batman movie in a suburban Denver theater.

Federal officials and local police in Aurora have said there was no indication the shooting was connected to terrorism.

Security at some movie theaters around the country has been increased after the deadly Colorado attack. This includes theaters throughout the District, Maryland and Virginia. And some events around the world for the premiere of the new Batman movie have been cancelled or scaled back.

Shortly after the shootings, police arrested James Holmes, a 24-year-old former neuroscience graduate student with no criminal record. The police say he shot scores of people and picked off moviegoers who were trying to flee the mayhem.

People who knew the alleged shooter described him as a shy and intelligent man who grew up in a well-to-do neighborhood in San Diego, Calif.

The intelligence bulletin, dated July 20, was distributed to law enforcement officials around the U.S.

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