The woman died after being dragged by the RTD light rail train at 24th and Welton streets.
Authorities say the incident happened at 1:03 p.m. The woman was described as a woman in her 20s. She will not be identified until her next of kin is notified.
Witnesses say the woman appeared to be intoxicated and was standing in front of the train trying to get the driver to let her on.
"She actually stood in front of the light rail to try to stop the train," Ryan Collins, a witness, said.
Passengers tell 9NEWS the driver made a motion to the woman, but it is unclear if it was meant to signal for the woman to move to the side or get onto the train. Some witnesses say the driver was motioning for the woman to get out of the way and others say it looked like he wanted her to get on board.
The woman then went to the side of the train and tried to open the doors using the buttons outside, witnesses say. They say the train started moving, and the woman was caught underneath one of the cars.
"I seen him gesture her like this and 'go around,' so as she gets to the side of the train, she starts to press the button and the train starts moving," Ruthie Landrum told 9NEWS. "She starts like spinning on the train, kinda like hitting the side of the train. And by the time the second car gets there, she bumps into the pole and just falls."
"She was standing in front of the light rail trying to block him from going until she got aboard, I guess. And she went to the side and that's when he took off," Collins said.
"She cleared the front of the light rail to the side and that's when the driver started to take off slowly and she must've gotten hooked to the side of the train," Mark Candelaria said.
"And by the time the second car gets there, she bumps into the pole and just falls," Landrum said. "I know he was motioning for her to come to get on the train because he went like this and told her to come to the side and nobody in their right mind is gonna walk up to the train try to press the button if somebody didn't tell them to get on."
RTD officials initially told 9NEWS the light rail is not supposed to let people on and off at 24th and Welton, which is near the 20th and Welton station, even if the train is stopped. A neighbor told 9NEWS the light rail lets people on and off at the intersection all the time when the light rail is delayed.
While 9NEWS was at the scene, our cameras saw trains stop several times at 24th and Welton, letting people on and off at the site.
"I've been able to get off plenty of times here," Landrum said.
Later, after 9NEWS told RTD spokesperson Daria Serna about our video of people getting on and off the train at the intersection, she said it is up to the light rail operators' discretion and they may allow passengers to get off the train when it's stopped for a long period of time.
RTD says it will review the incident, as it does after every accident.
Since the site at 24th and Welton was created in the mid-90s there have only been five accidents, including Tuesday's. Tuesday's incident was the only deadly accident at the location.
RTD was not cited for the four previous accidents.
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