Visitation held for slain Chicago Police Officer Aréanah Preston

CHICAGO (WLS) -- Tuesday begins two days of public mourning for Chicago Police Officer Aréanah Preston.

She was shot and killed earlier this month in Avalon Park while returning home from her shift. Four suspects have been charged in the shooting.

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"These wake up calls let us know that this job is literally different from one second to the next. It could be that quickly," said Chicago police union president John Catanzara.

Preston was an officer with the Chicago Police Department's Fifth District for three years.

Last Saturday, Loyola University posthumously presented Officer Preston's master's degree to her mother

Officer Preston's visitation began at 3 p.m. at the Blake Lamb Funeral Home in Oak Lawn. A steady stream of mourners attended the visitation.

"I was really sad. I cried. It's just really unfortunate that that had to happen. She was such a nice young lady," said Esther Hope, attendee.

Among those offering condolences was new Chicago Mayor Brandon Johnson, who was met at the funeral home by Interim Police Superintendent Fred Waller, and the sister of Officer Thomas Wortham who was shot and killed in front of his family's home 13 years ago this month.

"It hurts so terribly that Officer Preston died in this, in this very similar way. Why? For what?" said Sandra Wortham.

"She was doing everything right," said Cher Glenn, who knew Preston's family and whose own son is a police officer. "This is what I'm scared of, that it will happen to me. I bleed for her mother."

"This just proves how senseless these crimes are, not just because she was a police officer. It's just people are waiting for you to come home and rob you. It's more than said," said mourner Ernesta Ware.

The tragedy also comes weeks after the city was shaken by the deaths of firefighter Jan Tchoryk and Jermaine Pelt.

"We're all one big public safety family, and we all work together consistently, and we actually are friends and everything else, so it's tough for us to be going through this much so close together, a lot of trauma," said CFD Commissioner Annette Nance-Holt.

Officer Preston's funeral will be held at 10 a.m. Wednesday at Trinity United Church of Christ on the South Side.

We will have live coverage of the funeral Wednesday starting at 10 a.m. on ABC7 and on ABC7Chicago.com and wherever you stream.