NEW YORK (CBSNewYork) — Tragedy on the tracks.

A 21-year-old aspiring actress was killed by a train at the Union Square subway station early Saturday morning.

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On Monday, her mother held back tears as she spoke to CBS2’s Reena Roy about her daughter.

Helen McDonald-Phalon was full of love and light. The 21-year-old’s mother, Ann, told CBS2 by phone she radiated happiness wherever she went.

“She was just a gift,” Ann said. “She could walk into a room and within two-three minutes everyone in the room was happy and laughing.”

Unfortunately, on Saturday at around 3 a.m. she somehow came into contact with a No. 6 train while she was on a platform, officials said. She then ended up on the tracks.

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“I saw medical examiner moving body from 6 train,” witness Michael Humble said. “They shut down that line when they were doing the investigation.”

The Metropolitan Transportation Authority would not give CBS2 details on exactly how the incident happened. Investigators did say the platform was not crowded and the train had been moving for more than 100 feet before she was hit. They said it does not appear to be a side door drag and wasn’t an intentional act, but rather the MTA said it was a horrible and very uncommon accident.

“I think she tripped and fell and I think there was no protection,” Ann said.

McDonald-Phalon moved to New York from South Carolina after high school in 2015, graduating from a performing arts college in the city two years ago in the hope of making it as an actress.

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“I think every parent watches this in horror and you never wanna find out what it means to lose your child,” Ann said. “Every part of my body hurts … grief. Unimaginable.”