IE Paper Distribution Center Ignited By Arson, Morning Sky Darkens With Smoke, Ash

ONTARIO, CA — A massive warehouse fire at a one-million-square-foot Ontario warehouse and paper supply company drew a massive mutual aid response from Inland Empire firefighters early Tuesday, and was likely ignited by arson, officials say.

A worker at the facility, whose identity was not immediately released, was taken into custody in connection with possible involvement in the fire, Ontario Fire Department Deputy Fire Chief Mike Widdell told reporters at the scene. That individual was one of just over 20 workers who evacuated the building when the blaze began, according to Widdell.

Just after 12:30 a.m., a fire broke out at the Kimberly-Clark warehouse at Hellman and Merrill avenues in Ontario, according to Widdell. The Ontario Fire Department arrived to find the blaze eating through the interior, semi-truck trailers, and extending through the warehouse roof.

Over 140 firefighters worked the scene, which had the potential to extend into a nearby neighborhood. Firefighters battled the blaze in defensive mode, preventing spread to nearby homes. Inland Empire residents could see the thick column of black smoke for miles. Ash continues to rain down on the area surrounding the building as of 9 a.m.

"The fire has been contained to the building," Widdell said. "Smoke may be visible in the area, and ash is present, impacting air quality. Children and seniors should remain indoors if possible."

All residents were advised to avoid the area amid the firefight.

Hellman Incident Update: Fire is contained to the building as of 7:46 AM. Ash is present and air quality is impacted; children and seniors should remain indoors if possible. Please check https://t.co/Kl1UYsCdfw for updates in your local area on air quality. #ontariofire #hellman pic.twitter.com/qfBbQeWHcz

The San Bernardino County Fire and Cal Fire/Riverside County Fire departments arrived at the scene to assist the Ontario Fire Department, the lead agency on the attack.

The first-arriving unit reported heavy fire through the roof. Due to the heavy fire conditions, the Ontario Fire Department requested a second-alarm augmentation from several outside agencies, which brought in additional mutual aid resources, including over 10 engine companies, multiple truck companies, at least two battalion chiefs, and one division chief.

The Ontario Police Department used drones to obtain a full visual of the scene.

The building has suffered a complete roof collapse, and a defensive attack remains underway over five hours after the fire ignited. This report is still developing.

A Kimberly-Clark Products spokesperson responded to Patch about the devastation at the Ontario facility.

"We are aware of the fire at our distribution center in Ontario, California, earlier today. Safety is our top priority, and we can confirm there are no reported injuries," they said. "The facility is operated by a third-party partner, and we are working closely with them and local authorities. We will share additional information as it becomes available."

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