4 Saved, 1 Killed as Fire Ladder Collapses : Emergency: Firefighter is credited with saving two children after equipment buckles. Also surviving is the mother, but the father falls to his death.

A firefighter was cradling two children in his arms and guiding their parents to safety from a sixth-floor window in Brooklyn when the ladder they were on twisted and collapsed. The father leaped free, and died in the fall.

The mother, who was thrown clear, and their children, ages 4 and 6, were in critical but stable condition Monday. The firefighter’s condition was serious, a hospital spokeswoman said.

The ladder “looked like a pretzel,” said witness George Rosario, a baker. “I’ve got to give credit to the fireman because if he hadn’t been holding those kids, they probably would have been killed too.”

Firefighter Greg Smith was near the top of the lightweight aluminum alloy ladder Sunday when it buckled, throwing the mother, Aqueda Santana, 31, clear. The father, Yreno Espanoso, 37, jumped to his death. Smith gripped the children, Lissetto, 6, and Edwin, 4, and the three rode the ladder to the ground.

The crew had extended the 3-year-old ladder 91 feet up from the truck to reach residents trapped on the top floor of the brick apartment building.

Firefighters at the scene speculated that the weight on the top of the ladder might have contributed to the collapse, but officials said the ladder should have been able to bear the weight. They were investigating.

Investigators also will investigate whether proper procedures were followed. Officials said only one of the ladder’s upright posts was secured against the building, and firefighters might have been able to set up inside a metal gate to get a better angle, though that might have taken longer.

Deputy Fire Commander William Feehan said the setup was understandable given the urgency of the rescue effort, and did not violate department policy.

Ladders are used by fire companies across the country. They will continue to be used despite the accident, several big city fire departments, including New York’s, said Monday.

Seagrave Aerial, based in Clintonville, Wis., has “been in business for 100 years” and its ladders are used in every major city, said Tom Kniaz, chief of apparatus of the Detroit Fire Department.

On Oct. 27 in nearby Yonkers, a nearly identical Seagrave rear-mount ladder also twisted as firefighters battled a blaze. The only difference was that the Yonkers ladder buckled about 25 feet up while the one in Brooklyn twisted near the bottom.

One firefighter was injured in the Yonkers incident when the ladder crashed onto an adjacent roof. As in the Brooklyn incident, the ladder was fully extended, said Yonkers Fire Commissioner Neil Curry.

Seagrave Aerial would not give specifics on the ladder’s recommended use and company spokesman Joe Kaufmann would not offer details of the equipment’s safety record.