Kristyn Ulanday / for NBC News
Jennifer Anstead, a runner, had three friends injured in the marathon attack, including one who lost a leg.
BOSTON -- Scores of marathon runners, doctors, nurses and others descended on Boston on Thursday to join a memorial service to pay respect to the victims of the bombings that struck the iconic road race as the city continued to reel from the twin blasts.
Some nurses attended in their blue scrubs, while others in the crowd wore their blue-and-yellow Boston Marathon jackets. There were many large contingents of staff from the various city hospitals that responded to the trauma.
About 2000 people gathered at the Cathedral of the Holy Cross, less than a mile from the finish line, to honor the victims of the bombings that killed three and injured 176. NBC's Lester Holt reports.
Jennifer Anstead, a runner who was about 20 feet away from the second blast, choked up as she talked about three of her friends who had come to cheer her on and were injured in the explosions, including one who lost her leg.
"I still feel a lot of guilt. It's a lot to process. It's a lot to take in," she said.
"I'm trying to be strong for her," Anstead, a 37-year-old operating room nurse, said through sobs. Her friend has a "long road ahead," she added. "She's incredibly strong, she's an amazing person."
Another runner, Brian Ladley, said he found himself between the two bomb blasts but emerged unscathed. He appeared solemn and paused between words as he spoke with a reporter.
President Obama, addressing the crowd at the Cathedral of the Holy Cross, tells the people of Boston "your rebuke is the greatest resolve to whoever committed this heinous act."
"I'm here for the runners who can't be here today," said Ladley, 39, who just moved to Boston. "It's still surreal, but (I'm) coping, managing. It's good to be here with people ... people are coming together."
Rodney Bensley, a resident at Beth Israel Deaconess Medical Center who worked in the trauma unit as patients were incoming, said the last few days have been emotionally challenging, especially since a number of the victims were young.
"We personally cared for a lot of these patients and want to pay our respects to the ones that lost their lives and the ones that are injured as well as their families," said Bensley, 34, who waited with a long line of colleagues to attend the service.
"I kind of think about what happened and how to move forward and ... heal as a city," he added.
Registered nurses Linda Denekamp and Kim Cross, who work with Bensley, said the service offered a period of reflection for the staff.
"It's partly to decompress, partly to offer support to them and their families," said Denekamp.
"It's just nice to come here to take ... a step back and reflect," Cross, 26, added.
Kristyn Ulanday / for NBC News
Jennifer Dunphy, outside the memorial service: "I guess I'm just looking for ... maybe some peace, some understanding, something, a little bit of hope."
Another runner, Jennifer Dunphy, 29, stood in line with a friend who offered her a ticket to the service to help her cope with her feelings from that day. She said she was nearing the finish line as the blasts went off, and ultimately ended up crossing it as she searched for safety.
She later learned that some of her friends were hurt in the attack.
"You were numb at first, and then you're in shock and then you're angry,” said Dunphy, a political consultant and Charlestown resident. “Now I guess I'm just looking for ... maybe some peace, some understanding, something, a little bit of hope."
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