MINNEAPOLIS - A century-old condo building near Lake Calhoun was reduced to rubble on Fridayby afire investigators say began with a candle left unattended.

"It can burn all the way down when it's unattended," Minneapolis Fire Marshal Perry Edner told KARE.

"That wax can start on fire, which can spread to other material in the unit itself. Cats and dogs can tip them over, too."

All residents of the eight-unit condo escaped, with one treated for smoke inhalation.

"I looked in the kitchen and saw some smoke coming through," resident Ben Garber told KARE.

"I knocked on Josh's door and said I think this is for real."

Garber and Josh Socks both lived in upstairs units and quickly surmised the fire was below them.

"I looked out the back window and flames were shooting out, stuff was flying off the walls, and glass was breaking."

Garber and Socks ran downstairs to make sure other residents got out safely.

The three-alarm blaze sent smoke billowing through the Uptown area of Minneapolis at 8 a.m. and kept westbound traffic on Lake Street snarled for most of the day.

Andrea Johnson, who has lived in the building for10 years,said she called 911 after hearing an elderly neighbor down the hall screaming for help.

"After we saw that she was safe, I ran outside with my cat and dog," Johnson said in tears."And then, as I was carrying the cat,my cat jumps off my shoulder and ran back inside."

Johnson spent theprevious two days moving her ailing parent's antiques and memorabilia into her unit. It's all lost. So is her car, which was parked behind the 1912 building.

"There were letters from my mom, Christmas cards from my mom, and she's very sick now."

The blaze started on the first floor and spread quickly, according to the fire marshal. He said that,like most structures of that vintage, there were no sprinklers and nobuilt-in fire barriers.

The "balloon-framing" style of construction inthat era features one continuous outer wall.

"So the fire does get within the walls itself, and it won't stop on the first floor or the second floor. It continues to burn all the way up to the roof line," he explained.

"That makes the fire burn a lot faster and a lot hotter, and it's harder for us to put it out."

Once they were sure everyone escaped all eight units safely, firefighters had to switch to defensive mode.Crews from three different engine companiespoured as much water on the building as they could to save surrounding property, including a Dunn Brother's coffee shop next door.

Eventually they brought in a contractor toknock down theouter shell of the two-story building. All that remained by night fall were concrete steps leading to ahugepile of charred wood.

"We can do all the inspections and make sure all the things are up to code, but still it comes down to the individual residing in these buildings to be vigilant," Edner explained.

He pointed out that the fire prevention tips apply no matter how modern the structure is. Sources of heat -- candles, space heaters, cigarettes and kitchen stoves -- can't be left unattended.

"I wish I had grabbed more on the way out the door," Socks said.

"I didn't think to grab my titles or birth certificate or Social Security card.My photos, stuff on my computer, it's all gone."

One of the residents was with his grandchildren in Disney World and will return to find nothing.

Late Friday,the owners ofAmore Victoria, arestaurant down the street fromthecondo building, announced they'll be holding a benefit on Jan. 9 for the victims of the fire.

"We feel horrible these people lost their homes and everything they own," Jenna Victoria wrote to KARE. "Some of them were regulars and frequented Amore a few times a week."

Victoria said the restaurant staff will be organizing a "wish list" for victims, and will offer them free meals for the next seven days.