I'm a Northeastern student and live about a mile away from the explosions. When they took place, I was a spectator of the marathon and was about a quarter mile from the end.
Being that close to the finish line allows you to witness an amazing set of emotions as people push their bodies to the limit. It's truly inspiring to see folks cross the finish line and embrace their families.
When the bombs went off, I heard a huge bang (almost like fireworks) and everyone screamed. Most people around me freaked out and I assumed something was wrong. As the police arrived and tried to evacuate all the spectators and racers, the scene was absolutely chaotic. People were running left and right as law enforcement officials tried to have clear streets (to get to the victims). Eventually, we spilled out onto a much bigger road and I tried to call my parents (to reassure them) and get in touch with friends who were closer to the explosions. One was volunteering at the finish line.
Most people around me had terrible signal or a dead phone, so my phone was passed around a bit and a sort-of line formed for people who wanted to use my phone.
Eventually, I made it out and walked home. It was hard because of the mass of spectators and runners and the chaos in the area. I gave out my phone to anyone who needed it and donated my sweatshirt to a shivering runner, but eventually my phone couldn't connect either.
Over the rest of the day, Northeastern contacted the student body several times and urged everyone to stay inside. Dozens of calls and texts poured in from people I haven't talked to in months, and I underwent the painful process of calling friends.
It was an emotionally charged day and one I'll never forget. My thoughts and prayers go out to all those impacted by the explosions.
Read more accounts from people in the area on this page.More questions on Boston Marathon Explosions (April 2013):