KANSAS CITY, Mo. (AP) – Five firefighters were injured Friday morning while battling a blaze at a 1920s building that once housed vaudeville productions and showings of silent films.

The firefighters were hurt when there was a flashover inside the building, Battalion Chief Joe Vitale said. A flashover occurs when the contents of a room heat to their ignition point and simultaneously burst into flames.

One of the firefighters suffered burns on about 30 percent of his body, Vitale said. Four were still hospitalized late Friday afternoon, while a fifth had been released.

None of the firefighters’ injuries were believed to be life-threatening, Fire Chief Smoky Dyer said.

The two-story building houses a Kennedy’s Bar & Grill, a French bistro, a bridal shop and a clothing store. There were apartments on the second floor.

Tracey Snell, a barista at the French bistro, said the fire appeared to start at Kennedy’s. No one was there at the time. She alerted colleagues and called 911.

“Next thing you knew, all hell broke loose,” said Rosalind Morris, a co-worker.

The building was gutted but was still standing Friday afternoon. It opened in 1924 and had included a playhouse that later housed movie and theater productions.