Chicago (CBS) — Neighbors in Aurora marched along the streets for about four miles Sunday night, carrying memorials and the heavy burden of loss.

The pain echoed from the group huddled outside the Henry Pratt building.

Some emotional family members of the five innocent workers shot and killed in the mass shooting grieved.

They were surrounded by hundreds of friends, strangers and law enforcement who refused to let them suffer the excruciating loss alone.

Friday the company said 15-year employee, 45-year-old Gary Martin, was getting fired for workplace rules violations.

The shooting happened shortly after.

The business says their background check didn’t reveal Martin’s 1995 aggravated assault felony while he was in Mississippi.

While in Illinois, police said Martin was previously sent a letter stating he needed to voluntarily relinquish his firearm and FOID card.

Investigators are trying to determine how he remained in possession of the gun used in the mass killing.

Dan Alexander’s neighbor and friend, Russel Beyer, was killed in Friday’s massacre.

“They didn’t follow through on what they should have followed through on,” Alexander said.

Alexander asks where government safeguards were when a felon took out a gun he shouldn’t have had and took lives, including Beyer’s.

He said that has caused his grief to turn into anger.

One by one Sunday, each life lost was read aloud and offered a prayer by clergy.

Prayers were also offered for the five police officers who rushed in to stop the threat, were shot in the process and are now recovering.

Strangers consoling one another, in a community that can use all the hugs and comfort it can get.

The City of Aurora posted on Facebook that more than 1,700 people attended Sunday night’s prayer vigil.