NEW YORK (CBSNewYork/AP) — A 29-year-old woman plunged about 30 feet to her death off an escalator inside the famed World Trade Center Oculus, police said.

Jenny Santos, of Kearney, New Jersey, was on her way home when sources say she tried to retrieve her twin sister’s hat, which fell off while they were riding the escalator around 5:30 a.m. Saturday inside the lofty transit hub. She fell to the marble floor on the main concourse below.

Port Authority police spokesman Joseph Pentangelo said Santos was taken to Bellevue Hospital where she was pronounced dead. Police are investigating the incident.

At times struggling for words, Clemens Reinke told CBS2’s Brian Conybeare about the vibrant young woman who coached alongside him at the Bergen County Rowing Academy.

“It’s just hard to even believe this,” he said. “Just yesterday she was with us, Jenny was coaching our team.”

“Very gentle, caring, loving person, always ready to help,” he added. “She was beloved by all our rowers.”

Santos was a graduate of William Paterson University and a teacher. One friend described her as a “treasure” who will be missed by everyone who knew her.”

Reinke said he isn’t surprised she tried to save her twin sister’s hat.

“Somehow the hat flew away so that she would jump after that. That’s kind of her fun-loving way, also her helpful way of wanting to be helpful,” he said. “I can’t believe this went so wrong.”

The tragic accident left stunned visitors trying to make sense of it all.

“It had to be horrible for her sister standing right there. You know, it’s just dreadful, it’s just unbelievable something like that can happen,” Phyllis Herald, of Paterson, New Jersey, said.

Some wondered if safety rails or glass walls could have saved her.

“In my opinion, I think that they need to build the walls a little higher when they build these escalators, because the same thing happened at Shea Stadium when they rebuilt Shea Stadium. Someone fell over the escalators,” Juliana Herald, of Glendale, Queens, said. “The walls are not high enough to prevent tragic accidents like what happened today.”

The striking $3.9 billion transportation hub was designed by architect Santiago Calatrava and provides connections between New Jersey’s PATH trains and New York City’s subways and contains a shopping mall.

Its design is defined by its brilliant arched roof that’s meant to resemble a bird-in-flight. Inside, there are several layers of escalators each situated to end at almost a floating platform, leaving almost nothing between the escalators and the ground below, WCBS 880’s Mike Smeltz reported.

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