By Tim Jimenez

PHILADELPHIA (CBS) — On a 400-mile bike ride from our nation’s capital to Newtown, Connecticut, a group called “Team 26” stopped in Philadelphia Saturday morning. They’re riding in honor of the victims of the Sandy Hook shooting and all of those affected by gun violence.

Met by cheers from members of CeaseFirePa, Mothers in Charge and local officials, “Team 26,” rolled in their green cycling jerseys, stopped at the north apron of City Hall, where they were met by gun control advocates and public officials like Pennsylvania Attorney General Josh Shapiro and City Council President Darrell Clarke.

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For the fifth time, this group from Newtown is pedaling hundreds of miles to reach those who also want to see changes to gun laws in this country and even those who disagree.

One of the riders, Dr. William Begg, shared his story. He was in the emergency room the morning of the Sandy Hook massacre.

I witnessed the children of the Sandy Hook tragedy come in,” Begg said, “and when you see children who were shot a dozen times with assault weapons – they don’t survive.”

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Dr. William Begg (credit: Tim Jimenez)

He says gun violence is an epidemic and action is needed. From doctors like himself to nurses like his daughter.

“At her first day of nursing school here in Philadelphia, [she] called me and said, ‘dad, I saw a child who was shot and is paralyzed. I can’t go on.’ And I said, ‘no, you have to go on for the children.'”

After years of sitting on the sidelines, Dr. Begg says he and others in medicine have stepped up to address gun violence as a public health crisis.

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“When you witness the death of children in such a horrific manner it will motivate one to really try to make changes,” he said, “like I have committed to for the rest of my life.”