The crash happened at Cross Street and Broadway when the bus turned onto the woman as she crossed the street, Transit Police Superintendent Richard Sullivan told the Daily Voice. The bus was traveling at a low speed.
Chelsea resident Steven Vaccaro on Facebook captured the crash on his cellphone.
The impact knocked the woman to the ground, and the bus driver immediately stopped, police said.
The elderly woman was conscious after the crash but complained of neck, back, and leg pain. She was taken to a local hospital with non-life-threatening injuries.
"The MBTA has removed the bus operator from service while the investigation advances," an MBTA spokesperson said.
Transit police are investigating the accident.
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