WHITE PLAINS, N.Y. (CBSNewYork/AP) — All six of the people killed in a fiery collision between a Metro-North train and an SUV suffered blunt-force injuries and burns, a medical examiner announced Tuesday.

A brief statement released by Westchester County did not specify the cause of death for any of the victims. It also did not specify whether the blunt-force injuries were caused by the impact on the tracks or by the pieces of third rail that speared into both vehicles in the Feb. 3 accident.

The findings were based on autopsies conducted by the office of the county medical examiner, Dr. Kunjlata Ashar, the county said. The statement said Ashar’s final report and conclusions will not be completed until the National Transportation Safety Board finishes its investigation several months from now.

PHOTOS: Deadly Metro-North Accident

The collision killed five men on a Metro-North Harlem Line train and a woman whose SUV was hit by the train at a grade crossing in Valhalla. A fire erupted, apparently fueled by the SUV’s gasoline, and 12 sections of the railroad’s electrified rail pierced the SUV and the train car.

The train, braking hard, hit the SUV at 48 mph and traveled about 1,000 feet before coming to a stop, the NTSB said. The third rail penetrated the Mercedes SUV and then the first car of the train.

The train car ingested some 468 feet of the third rail, which split up into 12 pieces of 49 feet each, NTSB Board member Robert Sumwalt said.

The NTSB said it would use information from the autopsies and from surviving passengers’ injuries, coupled with a diagram of where people were sitting, to try to determine how people were killed.

The NTSB is also asking questions about whether Metro-North’s unusual third-rail arrangement, which involves taking power from the bottom of the rail, led to the splintering of the rail, which investigators said they had never seen before.

Another key question is why the SUV driver, Ellen Brody, was in the path of the train. A witness said her car was hit by the dropping crossing gate and she then drove forward and was hit by the train. The NTSB has said the crossing gates and lights were working properly.

Brody was a mother of three grown daughters and an active, outgoing member of her synagogue. She was “not risky when it came to her safety or others,” said family friend Paul Feiner, the town supervisor in Greenburgh.

The train passengers killed in the crash are Walter Liedtke, a curator of European paintings at the Metropolitan Museum of Art; Eric Vandercar, 53, a senior managing director at Mesirow Financial; Joseph Nadol, 42, a JPMorgan Chase & Co. executive; Aditya Tomar, 41, who worked in asset management at JPMorgan; and Robert Dirks, 36, a research scientist at D.E. Shaw Research in Manhattan.

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