(BOSTON) — A former Massachusetts police officer is accused of killing a pregnant 23-year-old woman who he began sleeping with when she was a teenager and staging her death to look like a suicide, a federal indictment unsealed in Boston on Wednesday alleges.

Former Stoughton police officer Matthew Farwell allegedly strangled Sandra Birchmore to death in February 2021 after she told him she was pregnant with his child and “staged” her apartment “to make it appear as if Birchmore had committed suicide,” the indictment stated.

He was indicted by a federal grand jury on one count of killing a witness or victim.

“We allege that Sandra Birchmore survived years of grooming, statutory rape and then sexual violence all at the hands of Matthew Farwell, who was employed throughout their relationship as an officer and then detective with the Stoughton Police Department. And when it became clear to Mr. Farwell that he could no longer control Ms. Birchmore, he silenced her permanently,” acting U.S. Attorney Joshua Levy said during a press briefing on Wednesday.

Farwell was arrested Wednesday morning and is scheduled to appear in federal court in Boston on Wednesday afternoon. ABC News has reached out to Farwell’s attorney for comment.

This is a developing story. Please check back for updates.

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