CEDAR FALLS - It's becoming an historic year for fires in the oldest part of Cedar Falls.

A Monday night fire left a landmark building downtown damaged, but intact.

A fire in the upper floors of the building at Fourth and Main streets injured no one, but damaged businesses on the first floor, including the Pump Haus Restaurant, Back Alley Bar and a U.S. Cellular store. Spontaneous combustion is being blamed as the cause.

Kitty corner from the building is an empty lot where another building burned Jan. 24. That fire started from an electrical wiring problem and destroyed the building. Four businesses were lost in the fire, and two apartments were also destroyed.

Firefighters were called to the Monday fire at 7:30 p.m. They contained the fire before it could spread through the building.

Owners of businesses in the first floor of the building are cleaning up today and hoping to open again soon.

The top two floors of the three-story building were unoccupied.

"We sustained a lot of water and smoke damage," said Johna Petersen, owner of the Pump Haus. "We're still evaluating, but we think we may be open again in about 10 days."

The Pump Haus, a restaurant and bar, had opened in October 2002.

The original emergency call came from that business.

Liz Cook was working at the Pump Haus when the fire started. She said the staff smelled smoke and originally thought it could have been from equipment in the kitchen. They ruled that out and then thought it could have been from a jukebox that had been out of order.

"One of the cooks came out of the building and saw flames coming out of the second floor," Cook said.

Cook estimated about 20 patrons were inside at the time and they were evacuated, as were patrons at the Back Alley Bar.

At about the same time as the Pump Haus cook stepped outside, Tim Schilling was working at Schilling Jewelers and saw flames on the second floor as well, just across the street from his business.

When firefighters arrived, flames were no longer visible.

"By the time we got there, the smoke had gotten so thick we couldn't see the fire," said Cedar Falls Fire Capt. Jim Boileau.

Visibility proved the biggest problem for firefighters, as they couldn't see to find the fire. They knocked down the main part of the fire from inside the building, then had the fire out by about 8:30 p.m.

The fire started on the second floor and spread into the third floor.

Firefighters believe the fire started on the second floor, where rags that had been used with a natural product such as linseed oil were left on the floor. According to fire officials, the cause was likely spontaneous combustion, which can happen with such natural products that are balled up.

The building is owned by Mikkel Mandt, and his son, Erick, has been working at restoring it.

It was the site of the original Oddfellows Hall. The third floor contains a large ballroom, and the ceilings there are 12 feet high.

The building had also housed the Olympia Candy Kitchen years ago. In more recent times it had been home to the Fourth and Main bar before a series of businesses including a spa and the current establishments.

In recent years, the Mandts have restabilized the building and were working at restoring the interiors. The second floor had previously housed apartments, but hadn't been used in about a decade. The third floor hadn't been used for a longer period.

The second and third floors under renovation did not have a particular business or purpose in mind.

Pigeons had called the upper floors home for many years. The owners had been working to control that problem, and earlier in the day Monday were installing additional pigeon strips, spikes that deter the birds from roosting on the building exterior.

Many of the pigeons didn't move from their roosts on the building, even as smoke poured out over them.

New windows had been installed on the building, and some of those had to be knocked out to control the fire Monday.

The fire department's aerial truck was used primarily to provide light to the interior of the building for firefighters on the inside to better track the fire. It was also used to break open a third-floor fire escape door to ventilate the building.

Janesville and Hudson fire departments provided assistance to the Cedar Falls Fire Department.

Staff writer Jeff Reinitz contributed to this article.