Two firefighters who saved two residents from a burning apartment building in Kansas City were killed Monday night after suffering injuries when the structure collapsed around them, authorities said.

Fire Chief Paul Berardi said two other firefighters were injured as the massive fire engulfed the block-long structure on the city's northeast side. Kansas City police and a response team from the Bureau of Alcohol, Tobacco, Firearms and Explosives are investigating the incident. The cause of the fire was not immediately clear.

Berardi lauded the bravery of the two firefighters who died and the scene was described as chaotic and apparently deteriorated quickly.

Fire Department Battalion Chief James Garrett told the Kansas City Star that the building was already heavily damaged when firefighters arrived. They were clearing an area where a roof had started to cave in about 7:30 p.m. when the building collapsed, Garrett said.

Tactical assignments were made and firefighters employed a rapid intervention team. The teams worked to suppress the fire and rescue occupants. The fire worsened and firefighters were forced to shift to "defensive" operations. In those instances, all firefighters are required to exit the structure and take a head count.

All firefighters were accounted for outside, and it is believed that at some point, the second floor collapsed into the building and the fire and debris essentially pushed the east wall out about 30 feet, trapping the men. Two Mayday calls were issued after a partial collapse. There were four firefighters trapped.

"It didn't fall like a normal collapse," Berardi said.

"The rapid-intervention team witnessed the collapse and held their ground for no more than 10 seconds," a fire official said at a morning press conference. They went in to rescue the trapped firefighters and located, uncovered and removed four firefighters from the area. The two firefighters, 17-year veteran Larry J. Leggio and 13-year veteran John V. Mesh, were pronounced dead at the hospital.

Leggio, an apparatus driver, leaves behind a wife and his mother. Mesh leaves a wife and four daughters.

"They did not die in vain," Berardi told KSHB-TV. "They saved two civilians, carried them out of the second floor on ladders, before the wall collapsed."

The loss was the department's worst day since six firefighters died in an explosion at a construction site in 1988. 

One resident who escaped the flames told The Kansas City Star that he was at home when he heard shouts to evacuate.

"I was laying down and heard somebody yell, `Everybody get out,"' Lee said. "I opened my door and there was smoke really bad."

A smoke alarm sounded, he said, adding that he was choking as he fled outside to safety. Mayor Sly James said he was praying for the firefighters.

"Tonight's tragic loss is a reminder that Kansas City firefighters put their lives on the line for all of us every day," James said in a statement. "Our condolences go out to the loved ones of those who made the ultimate sacrifice today."

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