One of the four sides of the iconic Gold Pyramid House in Wadsworth, Illinois, was severely damaged in a fire Tuesday.

Firefighters were called by an elderly man trapped inside the building along with his dog around 4 p.m. local time (5 p.m. EDT) but by the time they arrived, the person was rescued by a bystander. However, the dog remained trapped.

Firefighters had a difficult time searching for the dog due to the unique and confusing layout of the home. The third, fourth and fifth floors were engulfed in fire and several firefighters initially got lost in the house but were eventually able to find their way out. 

Fire officials later confirmed that the dog died in the fire and two–three firefighters suffered minor injuries. It took them more than three hours to douse the fire. A local resident said renovation works were going on in the house when the fire started.

The cause of the fire is still unknown.

In order to reach the house, the firefighters had to cross two bridges that go over the massive moat that surrounds the home. However, the moat turned out to be of help as they could draw water from it to fight the fire.

"From the ground to the peak of the roof, or to the point of the pyramid, there's a lot of void spaces in the walls," Gurnee Fire Department Battalion Chief David Douglass said adding this is the first time his department has ever fought a fire in a pyramid.

The fire damaged much of the north side of the building and left black scars along the west side as well. The extent of the damage to the interior of the home is not known.

Gold Pyramid House, an iconic six-story-tall, 17,000-square-foot home, is an architectural landmark located at 37921 North Dilleys Road. It was constructed by Jim and Linda Onan in 1982, Daily Herald reported.

"I told him I wanted to build a normal house," Linda Onan said in 2006 adding, "I didn't get my wish."

It was coated in 24-karat electro gold for almost 30 years but it had to be removed in 2011 because it was too blinding. Visitors have been allowed to tour the building, modeled after an Egyptian pyramid, for the past 17 years and this year’s tours were scheduled on Sundays from May 6 to Oct. 28. The building is filled with Egyptian artifacts including a 55-foot King Ramses II replica and a garage built to resemble three smaller pyramids.