The MBTA is investigating an escalator malfunction at the Back Bay Station in Boston on Sunday night that injured multiple people.
In a statement, the agency said the incident involved the escalator from the Amtrak/Commuter Rail platforms to the street-level lobby of the station.
Boston EMS said multiple units responded to the MBTA station shortly after 6 p.m., confirming nine people were injured and taken to local hospitals for treatment.
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It was not immediately clear why the escalator malfunctioned and officials have not said what happened. The MBTA said the escalator will remain out of service while the incident is thoroughly investigated, and signs were posted late Sunday night saying "Do not enter."
A representative for KONE, the company that inspects the escalators, said it is "working closely with the MBTA and other appropriate authorities to gather the facts and determine what may have caused the incident that occurred at the Back Bay station Sunday, and our thoughts go out to those who sustained injuries."
While Boston EMS said the injuries were minor, those injured and witnesses who were at the station when the escalator malfunctioned described a gruesome scene.
"It jolted, and I put my hand down, and as I put my hand down the escalator just started to free fall," said Sarah Aucoin, one of those injured in the accident. "We just started running up the escalator as fast as I could, and I looked back and everyone was just shredded and covered in blood and it was a horrific scene."
Aucoin and Claire Maia were in town from New Orleans with their husbands and friends to watch the Patriots-Saints game on Sunday. They had taken the MBTA Commuter Rail to Boston when the Back Bay Station escalator suddenly started going full speed in reverse.
"The steps were just rapidly going backwards. It was almost a little scarier because you had the edges of the stairs to contend with," Maia said.
Maia, who is five months pregnant, said she had just stepped off the escalator when she heard screams and turned to see her friends' terrified faces as they tumbled down the steep incline.
"I knew that they had a stop button, so I was just looking for the emergency stop button and I just kind of found it and I slammed it down and held it until it stopped," she said.
Eli Smith was waiting for his train to arrive when everything transpired.
"There was a whole bunch of commotion coming from this escalator, so out of pure curiosity I go over and look and there was like four people laying down and like a puddle of blood at the end of the escalator," Smith said.
He initially thought there was a shooting after seeing so many bloodied people.
"There was like a boy with his shirt covered in blood, an old woman that was like gushing, her face was covered in it. It was crazy," Smith recalled.
Smith says he asked personnel what went wrong and was told the escalator flattened like a slide.
"It's normally steps going up and then it turned into a slide, and then went backwards, and then that's when people fell," Smith shared.
The aftermath of the incident was referred to as a "medical emergency" on the MBTA Commuter Rail Twitter account. Numerous trains were delayed by the incident as transit police, Boston Fire and EMS all responded to the scene.
Aubrey Mixon was waiting for her train, as well, and wondered why it was delayed.
"A conductor came around and said that there was something happening at the station," Mixon said. "It's pretty crazy. I'm just glad it wasn't me."
Aucoin said she thinks her injuries and others would have been much worse had Maia not had the wherewithal to find the emergency stop button.
"I genuinely feel like people would have died had she not pressed that button," Aucoin said.