As the Mercury reported earlier this week, Portland fire officials have been fretting over the stalled apartment structure at SE Division and 37th Avenue, fearing it might attract the attention of vandals or squatters.

It looks like those fears were founded.

As first reported by Willamette Week, Portland police arrested three trespassers at the site early this morning. Among what police say were the group's drunken escapades: setting fire to a blueprint and spraying fire extinguishers around the structure.

Officers responded to a call of trespassing around 1:30 this morning, according to Portland Police Lt. Mike Marshman.

"We get out there and they're not even trying to be quiet," he said. "They're all 20-somethings and they're all drunk."

Police at the time had no reason to suspect a fire, Marshman said, and told the alleged trespassers to scale the fence surrounding the nascent building to face arrest.

Later this morning, a staff member at nearby Victory Bar was examining the previous night's surveillance footage and noticed bright lights and what appeared to be smoke coming from the structure. Fire officials were called out to investigate, and found the charred remains of a blueprint, Marshman said.

Whatever blaze occurred was minor, though, and the lights and apparent smoke in the camera footage were actually from the alleged vandals' flashlights and the fire extinguishers.

The building's developers—who have been mired in conflict with neighbors because the 81-unit structure doesn't plan to provide on-site parking — plan to hire security for the structure beginning tonight, according to Project Manager David Mullens. He said the building was not damaged.

Marshman called the crime "totally unrelated" to the controversies that have swelled around the structure in recent days. The fire bureau is investigating the matter, and will ultimately decide what charges to seek.

The Portland Fire & Rescue Bureau has eyed the building uneasily since a ruling last month led city officials to issue a stop work order. The bureau took the rare step of creating a response plan—typically reserved for completed structures—for the site.

"If this building experiences a fire, expect it to be a fast moving and dynamic incident," the document said.