High-res photo by runner David Green shows Boston Marathon suspect This photo -- taken by Boston Marathon runner David Green of Jacksonville, Fla., on the corner of Boston's Fairfield and Boylston streets at 2:50:15 p.m. Monday -- shows a young man in the lower-left corner wearing a white hat with a "3" on the side, similar to that seen in FBI-released photos. Green said FBI agents told him his photo was probably the best they had so far of the young man authorities identified as Suspect 2 in Monday's bombings that killed three people and wounded more than 175 others. BOSTON, April 19 (UPI) -- A high-resolution image believed to show a Boston Marathon bombing suspect is probably the best photo the FBI has so far, a runner who snapped the photo said. "I have spoken to several agents," David Green, 49, of Jacksonville, Fla., told The New York Times, "and they have got the photos, they are picking up material from me, and I don't think there's any doubt." The FBI had no immediate comment. Several hours earlier the FBI released fuzzy pictures and video of two young men who officials said they believed might be responsible for the Monday explosions that killed three people and wounded more than 175. Officials said they had images of one of the men putting a black backpack on the ground minutes before two near-simultaneous blasts went off near the finish line of the marathon at 2:50 p.m. One video, which officials said they did not release, shows the two men walking slowly away after a bomb exploded while the crowd fled. Green's photo, taken with his iPhone and time-stamped at 2:50:15 p.m. Monday, shows a young man wearing a white hat with a "3" on the side, similar to that seen in the FBI-released photos of the man the FBI called Suspect 2. Green told the Times and The Huffington Post he had just finished running the marathon and was walking to meet friends when two bombs exploded in front of him. He snapped the photo before rushing to help the wounded, he said. He posted the photo on Facebook later that day to share what he saw with friends who had expressed concern for his well-being, his Monday Facebook post said. But Thursday evening, after the FBI released images of the two suspects, one of Green's friends noticed the young man with the white hat in the bottom-left corner of Green's photo closely resembled one of the suspects. Green called the FBI. Agents told him his picture was probably the best they had so far, Green told the Post, echoing what he posted on Facebook Thursday night. That's because the photo was taken with a better camera than the others the FBI had, he told the Times. Green's Thursday night Facebook posting asks people to share the photo "as much as you can so that if someone knows this person they can turn them in." It had more than 8,000 shares early Friday, a United Press International check indicated.