3 killed and 9 injured in collapse of private hangar under construction at Boise airport, officials say

(CNN) - Three people were killed and nine others were injured when a privately owned hangar under construction collapsed on airport property in Idaho’s capital of Boise on Wednesday evening, city officials said.

The collapse of the metal structure happened at West Rickenbacker and Luke streets on the edge of Boise Airport’s airfield around 5 p.m. MT, and an investigation into what caused it is underway, the city’s fire department said Wednesday.

Of the nine injured survivors, five were in critical condition and receiving care at hospitals on Wednesday night, city officials said. The names of those killed and injured were not immediately released.

“There was a large-scale collapse of the building, the framework of the building. I don’t know what caused it, but I can tell you that it was a pretty global collapse that occurred,” Aaron Hummel, operations chief for the Boise Fire Department, said at a news conference Wednesday, before the city announced a death toll. “It was fairly catastrophic.”

The building under construction was not a city facility and airport operations were not affected, Hummel said. Hummel did not provide information about who was constructing the hangar.

First responders “found a hectic scene and worked to secure and rescue victims,” Hummel said in a Wednesday night release after the news conference.

Everyone in the area has been accounted for, Hummel said at the news conference.

“Boise police are working to help with the reunification of any family members,” Hummel said.

The construction was not an airport project, Rebecca Hupp, the airport director, said during the news conference.

The Idaho State Police earlier warned the incident was causing traffic issues near the airport on I-84 and urged motorists to drive through the area carefully and “stay alert.”

This story has been updated with additional information.

CNN’s Christina Maxouris contributed to this report.