BOSTON (CBS) - The second phase of the memorial to honor the Boston Marathon Bombing victims began Wednesday morning.
Four bronze poles will surround glass spheres of light at the Boston Marathon finish line on Boylston Street - the site of the bombing.
"It symbolizes the way we protect our ideas. How we cherish things that are very fragile," said Gloucester artist Pablo Eduardo, who designed the memorial. He said the strong bronze poles surround and protect the fragile glass spheres of light.
Eduardo said he hopes people will pass the memorial and take a moment to "learn about what happened here."
Planning began four years ago for the $2 million memorial, which has undergone a substantial redesign to satisfy the hopes and expectations of families who lost loved ones in the two bombings.
Three spectators were killed and more than 260 others were wounded in the April 15, 2013 attacks, and a Massachusetts Institute of Technology police officer later was shot and killed by the bombers as they tried to steal his gun.
The first phase was completed about two weeks ago.
There is no word on when the markers will be unveiled to the public.
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