A 19-year-old man jumped to his death on Saturday from the Vessel, the sculpture that is the centerpiece in the Hudson Yards development, the authorities said.

The leap around 6 p.m. stunned visitors to the 150-foot-high steel structure. Some onlookers screamed as they realized what had happened, witnesses said.

One person ran up to the body and covered the young man’s face with a jacket, the witnesses said.

The identity of the young man who died was not officially released, but classmates said he was Peter De Salvo, who graduated from Ridge High School in Basking Ridge, New Jersey, and attended Sacred Heart University.

They were stunned at the news.

“He loved rugby and football,” said Ethan Fain, 18, who had known Mr. De Salvo since preschool. “He loved to tell jokes.”