Updated at 6:25 p.m.

Someone likely intentionally set fire to grass in a Northeast Portland field Monday that grew to a four-alarm fire that burned two businesses, damaged at least five townhomes, torched around 50 parked cars and scorched four acres of brush, fire officials say.

During a news conference Tuesday, Portland Fire Bureau officials said they are seeking videos or any witnesses who saw anything suspicious on the site of an old driving range near Glenhaven Park along Northeast 82nd Avenue.

Lt. Jason Anderson, a bureau fire investigator, declined to say if it’s been determined how the fire was set and said the Bureau of Alcohol, Tobacco, Firearms and Explosives is aiding in the investigation.

He asked anyone with information to contact Crime Stoppers of Oregon at 503-823-4357.

Firefighters were still dousing smoldering materials inside a destroyed building near Northeast 84th Avenue and Russell Street as of Tuesday afternoon. The building had housed a boxing gym and a defunct athletic club, according to Portland Fire Bureau. Wind at times caused ash and dust to swirl in the air and led to a piece from the structure falling to the ground.

No one was injured in the fire.

A faint burnt smell was in the air as evacuated residents were allowed to return to their homes. Yellow caution tape blocked off parts of 84th Avenue to vehicular traffic.

Brandon Beck, who lives with his girlfriend, cat and dog in a three-unit townhome on the corner of 84th and Knott Street, said his home had only smoke and heat damage when they saw it the night before. The couple returned in the morning and had been told by firefighters that embers from the abandoned building across the street started a fire in their attic, which spread to a second-floor bedroom and a closet and torched their washer and dryer.

Beck, his girlfriend and dog were away from home when they learned of the fire. Their neighbors helped retrieve their cat, who was the only occupant at the time.

Beck, while looking at pieces of his ceiling on the second-floor carpet and charred wood and ash and soot all around, said he was glad they invested in renter’s insurance.

The couple and their pets stayed in a hotel the night before and Beck estimated they may stay there another month as they try to figure out their living situation.

They moved into the unit in December.

”What really hit home for me is having to start over,” he said. The couple said they have a GoFundMe page to help with expenses.

The damaged sites included The Lumberyard Bike Park, which offers indoor and outdoor BMX and mountain biking. On Monday, it said on Facebook that the full extent of the damage wasn’t immediately known.

“Our hearts go out in support to all those experiencing loss as a result of tonight’s fire," the business said. "We have immense gratitude for Portland’s fire, police, and emergency services; without their skill and courage, the toll would certainly have been worse.”

-- Everton Bailey Jr.

ebailey@oregonian.com | 503-221-8343 | @EvertonBailey

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