Chalabala/iStock(CHICAGO) — Four police officers who were injured during the active shooter incident that killed at least one in Aurora, Illinois, Friday are now recovering, according to a city spokesperson.

Aurora spokesperson Clayton Muhammad confirmed the condition of the officers to ABC station WLS.

Meanwhile, Kane County Coroner Rob Russell confirmed to ABC News that there has been at least one fatality from the shooting.

Few details about the nature of the afternoon shooting, which unfolded in a town about 40 miles west of Chicago, have been released.

Police, however, have confirmed that the shooter has been apprehended.

People who escaped the building when the shooting began have described the chaos inside.

“We got out of the back door as soon as we heard shots,” Howard Sebby told ABC News. “We saw one guy get shot, he was a co-worker, he was shot in the arm and back, I think they took him to the hospital.”

Sebby also said he saw the shooter "running," though it was unclear where the gunman may have been going. Sebby and another eyewitness, John Probst, said they were hiding out in a nearby home and being interviewed by police.

The city of Aurora, located about 40 miles east of Chicago, announced on its Twitter account that that alleged shooter had been caught.

"THE SHOOTER HAS BEEN APPREHENDED!" the tweet read.

EMERGENCY UPDATE | 3 p.m.
THE SHOOTER HAS BEEN APPREHENDED! The area is still on lock down!
More information will be provided soon.

— City of Aurora, IL (@CityofAuroraIL) February 15, 2019

Aurora police noted that the location has been "secured" but a "continued police presence will remain as investigation [sic] continues."

Active Shooter Incident has been secured. Shooter is no longer a threat to the area. Continued police presence will remain as investigation continues. Parents please contact your local school districts for dismissal plan https://t.co/P4y7X7K4og

— Aurora (IL) Police (@AuroraPoliceIL) February 15, 2019

Nearby hospital, Rush-Copley Medical Center, tweeted that they have received two patients who are being treated for non-life threatening injuries connected to the shooting.

Rush Copley is assisting those involved in the active shooter incident in Aurora. The hospital has received two patients who are being treated for non-life threatening injuries.

— Rush Copley (@rushcopley) February 15, 2019

The Chicago field office of the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) had announced earlier that it responded to the scene.

White House press secretary Sarah Sanders said that the president has been briefed and is monitoring the situation.

Sen. Tammy Duckworth, D-Illinois, thanked the "brave" first responders, and called it "a scary, sad day for all Illinoisans and Americans."

"I am monitoring the situation in Aurora, Illinois. This is a scary, sad day for all Illinoisans and Americans. Thank you to the brave first responders who risked their lives this afternoon and apprehended the shooter," she wrote on Twitter.

I am monitoring the situation in Aurora, Illinois. This is a scary, sad day for all Illinoisans and Americans. Thank you to the brave first responders who risked their lives this afternoon and apprehended the shooter.

— Tammy Duckworth (@SenDuckworth) February 15, 2019

Copyright © 2019, ABC Radio. All rights reserved.