Updated at 6:51 PM ET
This after a CDC advisory panel voted Wednesday afternoon to approve Pfizer's COVID-19 vaccine for use in 12-15 year olds.
The Food and Drug Administration (FDA) expanded the Emergency Use Authorization for Pfizer's vaccine on Monday.
Gov. Charlie Baker said there were about 400,000 people in Massachusetts between the ages of 12 and 15 in a press conference Wednesday morning. He said the state could start administering the vaccine to that age group as soon as Thursday.
Baker also said his administration was contacting the state's pediatricians to make sure they have a hand in getting the shots out to 12 to 15 year olds.
Massachusetts reached more than 3 million people fully vaccinated against COVID-19 on Tuesday.
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