Reactions have ranged from horror to thoughtful to wanting to take action:
The bravery and effectiveness of police is a blessing.Their presence is welcome, in times likethese. Yet it highlights something.
— ABFoundation (@ABFalecbaldwin) April 19, 2013
At least when we're receiving devastating news on twitter we have each other. Like an instant support group. Makes me feel less alone.
— Alyssa Milano (@Alyssa_Milano) April 19, 2013
Surreal. This is just huge. #manhunt #watertown
— mia farrow (@MiaFarrow) April 19, 2013
I probably wld have advised #UncleRuslan to lie low.I'd have been wrong.In this excruciating hour he showed us the best of human hearts
— mia farrow (@MiaFarrow) April 19, 2013
Does NRA stand for Nobody Remembers Anything?How many more of these events will we have to endure
— Bette Midler (@BetteMidler) April 19, 2013
My parents are being morning greeted by SWAT, friends have bullet holes thru their walls, grenades in front of houses #surreal #watertown
— Eliza Dushku (@elizadushku) April 19, 2013
Nighttime in #GoldCoast #Oz, have been glued to tv watching for hrs on end. Giving eyeballs a rest. My #hometown #Watertown stay #lockeddown
— Eliza Dushku (@elizadushku) April 19, 2013
My heart is w the victims. Big hugs to the cops I hear on the scanner. Stay safe
— Jeffrey Ross (@realjeffreyross) April 19, 2013people . "I love that dirty water, Boston you're my home".
wow...our FBI agents and police officers are badass... Don't mess with Boston..They are tough mother Fers
— Kirstie Alley (@kirstiealley) April 19, 2013
Whats happening in Boston is intense right now...
— JWOWW (@JENNIWOWW) April 19, 2013
Talking to my friends and family in Boston. Terrifying.
— Katie Couric (@katiecouric) April 19, 2013
In LA but thinking about Boston.
— Howard Stern (@HowardStern) April 19, 2013
RT @huffpostpol: Here are the Twitter handles of the Senators who voted against background checks huff.to/15gpUDV
— Elizabeth Banks (@ElizabethBanks) April 18, 2013
90% of Americans favor expanded background checks for gun buyers. Our senate failed. Our system is colossally broken.
— RainnWilson (@rainnwilson) April 18, 2013
sad day that we didn't pass background checks in U.S. Every responsible gun owner i know (and i know a lot) supported it.
— Rob Thomas (@ThisIsRobThomas) April 17, 2013
If 90% of senators wanted a double non fat vanilla cappuccino & we decided they should have a black coffee instead, they would be pissed.
— Jesse Tyler Ferguson (@jessetyler) April 18, 2013