By CBSBoston.com Staff

HOPKINTON (CBS) – The investigation into the death of 16-year-old Mikayla Miller in Hopkinton could take more than three months to complete, according to the Middlesex District Attorney.

D.A. Marian Ryan told the Hopkinton School Committee about the time frame during a meeting Thursday night, shortly after a vigil and rally was held for Miller on the town common.

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“Three months is fairly quick, actually, unfortunately. We have made efforts obviously, given the public interest around this, to try to expedite the process,” Ryan told the committee.

“No final conclusions have been reached in this case. We have made great progress in the two-and-a-half weeks but we are not anywhere near the end where we would be able to share with people these are some of the conclusions that we have.”

Ryan said the state’s medical examiner has not yet made a ruling in the case.

Monica Cannon-Grant, who organized Thursday’s rally calling for an independent investigation into Miller’s death, announced Friday that her non-profit organization Violence In Boston Inc. “just completed and paid for the process of Mikayla Miller receiving an Independent Autopsy.”

Miller, a sophomore at Hopkinton High School, was found dead April 18, hanging from a tree in the woods along a trail off West Main Street, which runs back to the apartment complex where she lived.

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Ryan said her office does not yet know how Miller died but she stopped short of calling it a suicide.

The D.A. came forward with new information Tuesday about the hours leading up to Miller’s death just days after Mikayla’s mother and Violence in Boston fueled theories that the teen was murdered or bullied to death because of her race or sexuality.

Ryan said any allegation of a cover up is “patently false.”

The D.A. said Miller and five other teens were involved in an altercation in the clubhouse of her Hopkinton apartment complex on Saturday April 17th. Mikayla told police she had been pushed and punched in the face.

Later that evening, Ryan said the health app on Mikayla’s phone logged 1,316 steps, the approximate distance between her apartment and where her body was found the next morning.

Investigators used cell phone evidence and witness interviews to determine none of the teens from the fight were with Mikayla during the hours she died.

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Ryan would not say if race played a role in the incident.

CBSBoston.com Staff