Annie Dookhan, center, leaves a Boston courthouse escorted by court officers and her lawyer on Oct 10. (Josh Reynolds/AP File)

In a court document, Massachusetts prosecutors say indictments are expected against a former state chemist accused of tampering with evidence in drug cases.

Annie Dookhan was charged in September with obstruction of justice and falsifying her academic credentials. An assistant attorney general said at the time that the charges were “preliminary” and that a “much broader” investigation was being conducted.

On Tuesday, a Boston Municipal Court judge granted a motion filed by state Attorney General Martha Coakley’s office asking that a pretrial hearing scheduled for Dec. 3 be rescheduled to Dec. 20. In the motion, prosecutors said the continuance was being sought because “a grand jury investigation is on-going with indictments expected” after Dec. 3.

Dookhan hasn’t responded to repeated requests for comment.

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