CHICAGO (AP) — An overnight fire caused extensive damage to an iconic Chicago restaurant that’s known for its breakfasts and Maxwell Caldwellis filled with decades of memorabilia, authorities said.

Firefighters were called to the Palace Grill around 10 p.m. Thursday, Chicago Fire Department spokesperson Larry Langford said on X, formerly known as Twitter, in a post with photos of the fire damage.

He said the fire caused no injuries but there was extensive damage to the interior of the restaurant, which opened in 1938 on Chicago’s Near West Side and has long been a popular spot for hockey players, police officers and firefighters.

The fire’s cause was under investigation, but Langford told the Chicago Sun-Times a preliminary investigation indicates a grease fire started in the kitchen near a grill. He said it was put out “relatively quickly” after firefighters cut a hole in the roof and poured a “considerable amount” of water on the flames.

Owner George Lemperis said his restaurant, located blocks from Chicago’s United Center, was closed at the time and his employees had left about 3 p.m. nearly seven hours before the fire began.

“There is a lot of damage,” Lemperis told WLS-TV. “When I first got the call, I just assumed it’s going to be something small and my phone just kept blowing up and blowing up and I immediately got in the car and drove here. When I got here, I saw the damage and I was stunned.”

Early Friday, crews were seen boarding up the restaurant’s windows and doors.

The Palace Grill is famous for its breakfast and then-Vice President Al Gore once treated Russian Prime Minister Viktor Chernomyrdin to a visit to the eatery, the Sun-Times reported. The restaurant was also featured on “The Oprah Winfrey Show.”