Boston Marathon Bombing: The Waves of Social Media Reaction
PHOTO: In this photo posted on Twitter by Mike Crockett, runners are seen stopped after two explosions occurred near the end of the Boston Marathon.

With the shooting at Sandy Hook Elementary School in December and Monday's bombing at the Boston Marathon, Americans have, unfortunately, become no strangers to hearing about tragic news and responding to it. And more than ever during these events, social media, including Twitter, Facebook and Instagram, have become the places people turn to find out about what is happening on the ground and how they can help.

As with the Sandy Hook shootings in Newtown, Conn., Monday's events played out on social media with similar waves of reaction and chatter, culminating with outpourings of support for the community that was hurt the most.

1. News Breaks

Ask most people how they found out about the explosions at the Boston Marathon and they will likely say through another person. They will also likely say that person was on Facebook or Twitter. At 2:59 p.m. ET on Monday, April 15, the Boston Globe tweeted:

BREAKING NEWS: Two powerful explosions detonated in quick succession right next to the Boston Marathon finsh line this afternoon.

— The Boston Globe (@BostonGlobe) April 15, 2013

The Globe's tweet had more than 10,000 retweets. ABC News and other news outlets confirmed the event on Twitter a few minutes later and the news spread at a rapid pace.

According to Topsy, a Twitter analytics company, at around 4:10 p.m. there were more than 300,000 mentions on Twitter of "Boston explosions." At around 4:30 p.m., there were more than 700,000 mentions on Twitter of the "Boston Marathon." Through retweets and shares on Facebook, the news got out that there was an powerful explosion in Boston and that a number of people had been hurt.

2. Details Emerge, Eliciting Strong Personal Reaction

In the second wave, details about the event spread. Everything from photos of blood covering the ground to a six-second Vine of the actual explosion was circulated, giving people a truer image of what had happened.

Can't believe this is happening - Very very graphic image of the Boston Marathon injuries deadspin.com/explosions-rep… #bostonmarathon

— Sean Moffitt (@SeanMoffitt) April 15, 2013

This Vine shows the blast itself: vine.co/v/bFdt5uwg6JZ #BostonMarathon

— Ezra Klein (@ezraklein) April 15, 2013

But it wasn't just graphic images and video of the event that spread, people shared their emotional reactions. Many also took to Facebook to search for friends they thought might have been at the event and posted that they were relived to hear everyone was OK.

My thoughts and prayers go out to everyone in Boston, can't believe what I am hearing/seeing.

— Samantha Giancola (@MTVsammi) April 15, 2013

Can't believe what's going on in Boston. Awful

— Chris Wolstenholme (@CTWolstenholme) April 15, 2013

I can't believe what happened. My prayers go out to the people of Boston right now.

— lindsey vonn (@lindseyvonn) April 16, 2013

3. Support Forms for Communities

All that was quickly followed by something seen in the aftermath of Newtown on social media - support for the community. Many people said that they were praying for friends, racers and the people of Boston. The hashtag #prayforboston trended on Twitter and Topsy reports that from 4:30 p.m. to 5:30 p.m. more than 75,000 tweets mentioned "Pray for Boston." People also shared photos of Boston on Instagram with the hashtag #prayforboston.

Pray for Boston.

— Diddy (@iamdiddy) April 15, 2013

Lets Pray for BOSTON.

— Wu Tang Clan (@WuTangClan) April 15, 2013

Others started to find out how they could give in different ways, including donating blood or their homes.

Just called MGH - they have enough blood on hand for the tragedy today, but will need blood later this week to replenish. #boston

— Amanda Soehnlen (@asoehnlen) April 15, 2013

Praying is good, but donating blood is necessary. Please RTRed Cross - 274 Tremont Street •Boston, MA 02116 Phone:1-800-RED CROSS

— Clinton F. Barton(@_ClintBarton_) April 15, 2013

Thousands shared the link to Google's People Finder on Twitter and Facebook and some even began to circulate a Google Document with a list of people who were offering up their homes to people in the city.

And the reaction and the support for the community continues today as people spread messages about wearing purple Wednesday to support the city and attempt their own investigations into who could have been behind the blasts by examining this photo of a "mystery man" who was on a roof near the explosions Monday.

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