The MBTA is launching an investigation after the doors of a Green Line train closed on a woman while she was trying to help her son off the trolley.
Rebecca Mason posted on social media about the incident that happened at Medford/Tufts station on January 1.
"Just had a terrifying experience on the MBTA Green Line. I was helping my 4 year old get off the train and my leg got trapped in the door!" Mason wrote in her initial post about the incident on X, formerly known as Twitter.
"Thankfully my son was not hurt and I'll probably have a big bruise at worst." Mason said as she confirmed she escaped with a minor injury but refused medical attention.
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In a statement to Boston.com, the MBTA says their preliminary findings say that standard operating procedures were not correctly followed by the operator.
The MBTA said the operator shut the trolley down before checking if every passenger had gotten off. When the train is shut down, the doors don't automatically reopen, the agency said.
“This experience for any passenger is unacceptable, and we want to assure the public that a swift yet exhaustive review is being conducted,” the MBTA said to Boston.com