ETNA (KDKA) – Crews spent hours fighting a seven-alarm fire at a warehouse in Etna Wednesday.

Firefighters were sent to the STORExpress warehouse on Hafner Avenue around 2:30 p.m.

Heavy smoke poured from the building and flames could be seen coming through the roof.

“This is crazy, I can’t even breathe right now,” said Rutger Meixner, a bystander near the scene of the fire.

Smoke in Etna was so thick that Meixner said, “Fireman are disappearing in front of me.”

KDKA’s Amy Wadas reports —

It took firefighters almost three hours to contain the fire. They consumed all the water in the town, knocked out power to the neighborhood and evacuated residents surrounding the warehouse.

The large-scale building, which serves as a storage facility for vehicles and boats, proved to be a challenge for first responders.

“Everything above on the second floor concrete, including antique cars, very nice cars stored upstairs, has all fallen down into the first floor, which has created a very significant problem for us to try and deal with,” Etna Fire Chief Greg Porter said.

Porter said the amount of fuel in the building only made matters worse.

“There was a significant amount of fuel, which actually early on in the fire exploded and pushed the front wall of the building out,” he said.

Porter believes somebody may have been working on a motorcycle inside the warehouse and it may have caught fire.

KDKA’s Brenda Waters reports —

The fire marshal is still investigating the cause of the fire, along with why the fire alarm never activated and why the sprinkler system malfunctioned.

Three firefighters were taken to the hospital with minor injuries.

KDKA’S Lindsay Ward reports —