A frightening incident occurred on the Second Avenue subway line Monday when a 92-year-old man fell on one of its escalators.

Mauro Lucentini was riding up the center escalator at the brand new 72nd Street station just before 1 p.m. when he lost his balance and went tumbling back down the moving steps.

“I don’t know what happened,” said the frail man, who was pushing a little cart. “The stairs just moved away for me. I just slipped on one step.”

Another straphanger immediately pushed the emergency button, and the escalator jolted to a stop.

Lucentini, who said he writes for an online Italian newsletter, said he was achy but felt okay. A doctor who was standing nearby called emergency services, and an ambulance came to take him to a hospital.