The evacuation order issued after yesterday's auto yard tire fire has just been lifted.

Since 2 pm this afternoon, air quality monitors have been reading typical air quality standards, and at 5 pm Portland Fire and Rescue gave the "all clear" for evacuated residents to return home.

The fire—which started around 9 am and sent toxic smoke into Northeast Portland—displaced four families, killed 16 cats and triggered a mandatory evacuation of roughly 1,400 nearby residents.

The four family dwellings consumed by the fire included one duplex and two detached homes, Portland Fire and Rescue spokesperson Louisa Jones said in a press briefing earlier this afternoon.

The cause of the blaze is still under investigation.

Jones added that rescue crews were using about half a million gallons of water per hour at peak efforts of fire containment yesterday—with the goal of keeping flames away from a large pile of tires and propane tank, both of which could have triggered explosions.

"It was a terrible incident," Jones said, "but it could have been much, much worse."

After a mandatory evacuation due to compromised air quality last night, 140 people, including 70 children, sought emergency shelter.

Those residents that returned home today are being asked to thoroughly clean their belongings of soot in order to remove toxic contaminants.

The Oregon Department of Environmental Quality (DEQ) Northwest Region Clean Up will also be working with the county and residents to assess water and soil toxicity in the area surrounding the blaze.