Landmark Square fire lit up Sheboygan's night sky in 2007. Its cause remains a mystery.

SHEBOYGAN - One of the city's largest fires was sparked in 2007 by multiple explosions that destroyed the unfinished four-story $13.25 million Landmark Square senior living center downtown.

The city's skyline glowed orange from the fire's blaze on that early March morning, forcing the evacuation of 139 residents of a nearby nursing home and injuring two firefighters.

The fire was first reported at 4 a.m., and by 6 a.m., it was contained.

The fire department sent 18 firefighters to the scene initially. Eventually, some 27 city firefighters were at the scene along with seven fire engines. Units from other fire agencies and additional staffing arrived later on the scene.

According to retired firefighter Dean Klein: “When we arrived, the entire second floor was in flames. Just by chance, as I rolled up, the west side of the building had exploded and windows went flying across the street, glowing orange on the sidewalk."

According to the Sheboygan Fire Department, besides the partially constructed building, nine different properties and at least one vehicle were damaged by the blaze.

A 2007 Press clipping from Katie Reilly of the Sheboygan County Historical Research Center said an area resident who lived a few blocks away from the blaze told the Press he saw a person dressed in black run past his house, across the street and through a narrow alley in the early morning darkness, just after the explosions.

While there has always been talk of an arsonist starting this fire, according to Sheboygan Fire Department's Nicholas Noster, the cause of the fire to this day is undetermined.

Noster added that while there was talk of it potentially being suspicious in nature, neither the State Fire Marshal's office nor the ATF has closed the investigation.

After the smoke had cleared from the blaze, the executive board of Landmark Square decided to rebuild the structure that was destroyed.

At the time, according to a Press clipping, the executive director of Sheboygan Senior Community, which owns Landmark, said, "We need to get all our ducks in a row, obviously, and we're a little early in the process, but the intent is to rebuild."

At the time of the fire, there was about $9 million worth of work done at the complex.

The road to getting the Landmark rebuilt had a few potholes in the road when contractual payments the city was to make were interrupted by the fire.

Landmark, according to a Press article, had to have a certain value to receive the payments. The fire interrupted the payment schedule as the value was changed.

Many future residents had to change their moving plans for their new apartments as a result of the fire.

Today, the rebuilt Landmark continues to serve the senior community.

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This article originally appeared on Sheboygan Press: Sheboygan Landmark Square fire remains a mystery after 15 years