In the video, the girl appears to be alert as she crawls out from under the train, her pink backpack briefly catching on the car’s underside before the two men hoist her onto the platform, which is packed with rush-hour commuters.

One of the men who helped the girl off the tracks, Antonio Love, 32, said that he had been walking near the Kingsbridge Road station when he heard people screaming. He said that when he ran up to the platform, he saw that another man was already trying to help the girl.

Mr. Love said that when he jumped onto the tracks, he saw Mr. Balbuena-Flores’s body beneath the train’s wheels. The girl was crying and there was blood on her head, Mr. Love said.

“The only thing she was saying was ‘Papa, my papa,’” he said.

The two men called to the girl, Mr. Love said, and she soon crawled toward them.

Mr. Love and the second man were taken to St. Barnabas Hospital in the Bronx with minor injuries, the Fire Department said.

At the hospital, Mr. Love, whose yellow sweatshirt was stained with blood, said he was just “a little banged up.” Mostly, he said, he was shocked by what he had seen.