"As long as the event happens in a public space, there's no way to stop over-the-top or inappropriate information from getting out there," Weide said.
For sure, Twitter, Facebook and other social media sites were a useful source of information for many tracking the events. Google set up a Person Finder, as it did after the Japan earthquake two years ago, to help people connect with friends and loved ones after the incident.
Not surprisingly, the hashtag #bostonmarathon spiked sharply almost immediately after the attacks, said Hashtags.org, and mentions of "Boston" soared on Facebook, reported analytics company Topsy.
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