Synopsis
On April 15, 2013, two bombs exploded during the Boston Marathon about 2:50 p.m. EDT on Boylston Street near Copley Square, just before the finish line. The blasts killed 3 people and injured at least 176 others (for more general information, see the Wikipedia Article). This became an immediate complex problem for police and responders - treating the injured, the possibility of secondary devices, and securing the crime scene.

Use of radio channels
An online feed of two-way radio traffic from the Boston Police Department was available throughout the incident; recordings are available on Soundcloud and in a DAN News article. Broadcastify also later made available recordings of the Boston Police Department and Fire Department feeds from around the time of the incident. Listening to the police and fire scanner feeds is interesting in the difficulties of using "low bandwidth" voice - note how police quickly allow only a single point of reporting; on fire channel how mass casualty incident emerges, how Unified Command Center (UCC) is notified, integration of the (later found to be unrelated) JFK Library fire, and lack of interoperability (at least at the ground level) between Police, Fire and EMS. Later (around 19:00 minutes into recording on fire) channel allocation seems to get worked out quite well - Channel 2 for command (UCC), Channel 4 for operations (see Radioreference for channel allocations). Also note CPR being reported, and no obvious use of START Triage.

Infrastructure impact
Many cellphone networks became inoperational during the incident: at the time, it was thought that networks were shut down to prevent remote detonation of further devices, but it was later claimed that the networks were simply overloaded. Scanner feeds indicated this caused problems for first responders and law enforcement, as well as for the public trying to contact friends and relatives.

Social media usage
Social media for good post: a variety of interesting observations on the use of Facebook, Twitter, Geofeedia, and Flipboard, including: Facebook worked well for "safe and well" messages, probably better than dedicated tools like Google Person Finder and Red Cross Safe and Well because it is a tool everyone goes to by default, and it didn't get overladed; and the fact that social media seemed to provide information around 15 minutes ahead of CNN, but no less coherent.

PTSC post by Patrice Couliter: the emerging importance of aggregation and curation tools like Storify (see example Storify page), Reddit (see screenshot) and Rebelmouse and issues with cellphones

A blog post on the iDisaster site examines who tweeted what when, notes that tweets don't need to be "polished" and that good information seemed to get retweeted more than bad, which was ultimately corrected.

Of particular interest in this incident, there were clearly thousands of people taking pictures of the marathon before and during the event, many being posted on social media. This prompted the FBI to request the public to submit all photos and videos taken of the event to them.

Social media was heavily used in the later days, in particular during the "Boston lockdown" incident on April 19. Huffington Post had a live blog. Interestingly, Boston Police made a request for media (and social media) to not broadcast locations of the search for suspects - this resulted in live scanner feeds being brought down.