MORRIS, Ill. (CBS/AP) — Officials in the northern Illinois community of Morris say enough progress has been made in battling an industrial fire to allow thousands of residents who were evacuated three days ago to return home.

Fire Chief Tracey Steffes says there is no active burning at the building that contained 100 tons of batteries.

READ MORE: As Lollapalooza Ends, Concerns About The Spread Of The COVID-19 Delta Variant Begin

The burning batteries were smothered with 28 tons of cement.

Firefighters resorted to the unconventional and possibly unprecedented tactic because using water or firefighting foam could have caused the batteries to explode.

READ MORE: Chicago Weather: August Starts On The Cooler Side

He says firefighters are closely monitoring the fire because there remains a chance the batteries could start burning again.

On Thursday, the Illinois EPA asked the Illinois Attorney General to take legal action against the owner behind the lithium  battery fire in Morris.

People living in parts of Morris had to evacuate Tuesday because of an industrial fire involving lithium ion batteries, and the evacuation has been deemed mandatory for 24 hours.

MORE NEWS: Chicago Weather: Slight Chance Of Storms Overnight; A Quiet Pattern To Come

Copyright 2021 The Associated Press. All Rights Reserved. This material may not be published, broadcast, rewritten or redistributed.

CBS 2 Chicago Staff