CHICAGO (WBBM NEWSRADIO) — West suburban U.S. Rep. Peter Roskam was among the Republican lawmakers aboard the chartered train that hit a garbage truck Wednesday in Virginia.

Roskam said at first all he felt was a bump. But he said it quickly became obvious what they had hit.

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He told the WBBM Noon Business Hour that within moments members of Congress and their families who are doctors and nurses, and aboard the train, began making the rounds in the train and on the ground.

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“What impressed me was how quickly and how intuitively the doctors and nurses were…almost walking out of instinct,” he said.

Roskam said their quick reassurances helped maintain a sense of calm aboard the train, which was bound for a policy conference at the historic Greenbrier resort in White Sulphur Springs, W.Va. He said several of the doctors and nurses disregarded Amtrak crew requests to stay on board so that they could check on those who had been aboard the garage truck.

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U.S. Rep. Roger Marshall (R-Kan.) performed cardio-pulmonary resuscitation on a member of the Amtrak crew. The exact number of those treated and transported was not immediately clarified, although Roskam said that no members of the Illinois delegation were hurt.