HOUSTON – A structure collapse in a burning building killed four Houston firefighters, the deadliest fire in the history of the country’s third-largest fire department, officials confirmed in a statement Saturday.The four firefighters – Capt. Matthew Renaud, Engineer Operator Robert Bebee, Firefighter Robert Garner and Probationary Firefighter Anne Sullivan – were responding to a five-alarm blaze reported around noon Friday at an Indian restaurant in southwest Houston that soon spread to a neighboring hotel. More than 200 firefighters eventually arrived to fight the blaze, officials said.Houston Fire Chief Terry Garrison and Mayor Annise Parker said during a Friday briefing that at some point, a wall inside the burning buildings collapsed on the firefighters who died. Saturday’s statement reiterated that the deaths stemmed from a “collapse,” and a Fire Department spokesman said it was best described as a structure collapse.Three firefighters died at the scene, while a fourth was taken to a nearby hospital and later died, officials said.As of Saturday, 14 additional firefighters had been hospitalized in connection with the fire, according to a Fire Department statement. One was in critical condition and another was undergoing surgery Saturday, the statement said. The rest were stable, some enough to be released Saturday, the statement said.Authorities were still trying to determine what caused the massive blaze.“The scene is currently secured and under investigation. The Houston Fire Department arson division is the lead investing agency on this incident with assistance from the State fire marshal office, (federal Alcohol Tobacco, Firearms and Explosives) and Houston Police Department,” the statement said.