Heavy rains and wind ... couldn't keep THOUSANDS from gathering in Boston to mark ONE YEAR since the bombings at the city's iconic marathon. At 2:49 this afternoon... a flag was raised, followed by a moment of silence and the ringing of church bells: 2:49 is when two bombs went off at the marathon's finish line ... Three-people were killed... and more than 200-others were wounded... the youngest victim was just 8-years-old. Vice President Joe Biden spoke during a ceremony to remember the victims and the survivors. 3 When the bombs went off - a local man tells us he WITNESSED the chaos that followed. He snapped a photo - a picture that ultimately helped the FBI identify one of the suspects. Channel 4's Bruce Hamilton shares David Green's story. 3 00-05 19-24 1'43-2'00One year ago today he crossed the finish line at the Boston Marathon. One year ago today he witnessed the bombings that forever changed his and the lives of many others.One year ago today he snapped a picture that would help the FBI identify one of the suspects in those deadly bombings. SOT40:45 - Time slowed down for me and I knew I needed to do something. I took that one photo and wanted to see if I could help. It's really a gut instinct to do something, it has nothing to do with a hero. I can tell you I saw plenty of heroes that day. 41:00That's Dzhokhar Tsarnaev one of the two Russian brothers who the FBI pegged as the bombers. David Green of Jacksonville snapped the photo spontaneously..... and it wasn't until he thought about it days later that he realized he had a key piece of evidence the FBI would want to see. SOTApprox 43:45 When I came home, the next couple days, there was nothing to do with my photo. There was a security video that popped up with those two suspects, a very grainy video, you couldn't see much detail. My local friend Jason called me and said Dave, look at your photo you posted on Facebook. Looks like a guy with a baseball cap, you can see him clearly walking away from that bomb site.That's not all Green saw. He witnessed something jarring...something that left an indelible image on his mind's eyeSOT41:02 - The girl Jane Richard who ended up losing her leg could have lost her life I think because she was lying on the street missing her leg and an off-duty firefighter, who just happened to be there, ran in. I watched him pull a belt off somebody who was running and tourniquet her leg and probably saved her life. 41:21 If you would like to watch David Green's entire interview from The Morning Show - go to news-4-jax- dot-com. We've posted it inside the story ...Look under our top stories.