Federal authorities are not aware of any "specific, credible information" indicating a terrorist threat for the July 4 celebrations, but have urged local officials to take "protective measures" on the first major holiday since the Boston Marathon bombing, according to an intelligence bulletin.
The bulletin, sent to local law enforcement Tuesday by the FBI and Department of Homeland Security and obtained by ABC News, says the July 4 celebrations are "potentially attractive terrorist targets due to the presence of large crowds, the potential ease of access at locations hosting holiday events, and the symbolic nature of the holiday."
In past years such bulletins have become somewhat routine ahead of major U.S. holidays, but this year's Independence Day marks the first national major national holiday since the Boston Marathon bombings in which three people were killed - including an 8-year-old boy - and more than 260 others injured. As ABC News reported in May, sources said the alleged perpetrators of that attack originally planned to target Boston's massive July 4 celebrations but moved up their timeline after constructing the explosives.
The joint FBI/DHS bulletin comes just days after the agencies issued another notice reminding law enforcement that fireworks could be used to build bombs, as they allegedly were in the case of the Boston Marathon attack.
According to FBI officials, homegrown terrorists and other extremists acting on their own "are of paramount concern" this Fourth of July as masses of revelers are expected to pack city centers and other locations. The officials worried such "crowd density" could be an "opportunity to perpetuate a mass casualty attack," as illustrated by the Boston bombings.
Security officials in Canada announced Tuesday they had thwarted a planned mass casualty attack that would have taken place outside a government building in British Columbia on Canada Day, a major holiday for that country.