Moments after a gunman opened fire on the Seattle Pacific University campus in June, social media exploded as people took to Twitter and other networks to report what was going on.
A number of students tweeted where they were sheltering, while other people posted pictures of the scene unfolding as police swarmed in.
Although a heroic student was able to quickly incapacitate the gunman after he shot several people, Officials worry all of the postings could have ultimately led to a much greater tragedy.
"Sooner or later we'll have an emergency where the suspect is watching social media. That could allow an offender to escape, or possibly even cost an officer their life," says Washington State Patrol Chief John R. Batiste.
After other recent shootings in Moncton, New Brunswick and Portland, OR, a number of Puget Sound area agencies decided they needed to do something to get the word out about the potential dangers of sharing too much during an emergency, launching a new campaign this week called "Tweet Smart."
"We had seen agencies try to do that in the middle of an emergency. They've got the active shooter running around and they're seeing people posting stuff and they're saying 'please don't do that'...and the cat's already out of the bag," says WSP spokesman Bob Calkins. "So our goal was to get out ahead of that and make it a part of social media culture."
It's a growing problem that first came to light for local law enforcement following the November 2009 shooting of four Lakewood police officers. As Seattle police surrounded a park in search of suspect Maurice Clemons, a number of people reported police movements on Twitter.
"If he was there or paying attention and watching a hashtag, that is absolutely the kind of thing that could become a problem," Calkins says.
Mainstream media have worked with law enforcement for years to limit the reporting of sensitive information during critical times. But with the prevalence of smartphones and social media, there can be hundreds of people posting information and photos in real time.
"When we're on big scenes that draw a crowd, almost immediately you see the arms go up with the cameras, which is fine. It's what you do after that's the problem," says Asst. Chief Mike Zaro with the Lakewood Police Department.
"I don't think they're doing it maliciously. I just think they haven't been made aware of what some of the risks of that are," he says.
The "Tweet Smart" campaign is a partnership with a number of law enforcement agencies including the WSP, Bellevue, Des Moines, Federal Way, King County, Kitsap County, Lakewood and Seattle.
Officials say they're not trying to deter people from posting pictures altogether, but to avoid posting officers' movement and other tactical information that could put lives at risk.
"If it's safe to do so, go ahead and take pictures of our deputies in action," says Kitsap County Sheriff Steve Boyer. "We're very proud of the work they do. We'd simply ask that you wait to post those pictures until the emergency is over."
The campaign includes a list of suggested do's and don'ts law enforcement hopes people will keep in mind during an emergency:
-Do get to a safe place and call 911 if possible. Live telephone calls to dispatchers are law enforcement's best source of real-time information in an emergency.
-Do feel free to let family and friends know you've reached safety.
-Do feel free to warn friends if you have first-hand knowledge of a developing emergency.
-Don't tweet or post about the movements of police, or post pictures of officers. Even what seems like vague information could be used by a criminal familiar with the area.
-Don't endanger yourself to get a picture, no matter how compelling.
-Don't spread rumors. If you're not sure, don't post, tweet or re-tweet.
-Do feel free to tweet about the response and post pictures after the emergency is over.
Calkins acknowledges the campaign won't completely stem the tide of social media during an emergency, but he says law enforcement hopes it can start a conversation that will make people think twice before posting in the middle of an unfolding incident.
"The "Twittershpere" has a very strong culture. We're hoping to make this safety item a part of their culture," he says.
KIRO Radio's Jillian Raftery contributed to this report.
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