7,000 children's shoes laid out on Capitol lawn to honor lives lost to gun violence

Seven thousand pairs of children's shoes were lined up on the southeast lawn of the U.S. Capitol building in Washington, D.C., Tuesday in memory of every child who has died due to gun violence, the global advocacy organization Avaaz, who coordinated the display, said.

The 7,000 shoes in the "Monument for our Kids" installment represent every child that was killed by gunfire since the deadly shooting at Sandy Hook elementary school in Newtown, Connecticut, in 2012, according to Avaaz.

"We are bringing Congress face to face with the heartbreak of gun violence," Oscar Soria, a senior campaigner with Avaaz, told ABC News. "All of these shoes cover more than 10,000 square feet."

Though most of the shoes were collected in a two week period, some of those were donated by families that lost their children to gun violence.

"About five families came that were victims of gun violence," Soria said. "It was an emotional moment today."

One of the parents in attendance Tuesday was Tom Mauser, whose son was killed in the Columbine school massacre.

"I'll be traveling to D.C. literally wearing my son Daniel's shoes, the ones he wore the day he died at Columbine," Mauser said, according to a statement from Avaaz. "I think this kind of event with shoes offers a very powerful metaphor both for how we miss the victims who once filled those shoes and also for how we see ourselves wanting to walk in their place, seeking change, so that others don't have to walk this painful journey."

Also in attendance was Andy and Barbara Parker whose daughter, Alison, was shot on live television in 2015 while doing a news report for CBS affiliate station, WDBJ, in Roanoke, Virginia, Avaaz said in the statement.

The organization also said that some celebrities donated shoes as well, including Bette Midler, Susan Sarandon, Alyssa Milano, and Chelsea Handler.

"It's amazing to see," Soria said. "People are just coming and taking pictures and just looking at this reflection of gun violence."

The shoes will be taken off the lawn around 2 p.m. Tuesday, but Soria said that all 7,000 pairs will be donated to charity.

This isn't the first display addressing gun violence from Avaaz.

In February, the advocacy organization put up a trio of mobile billboards by Sen. Marco Rubio's home in Miami, Florida. The billboards asked why there was no congressional movement on gun control, with one of the billboards reading, "How come, Marco Rubio?"