A former Massachusetts police detective is accused of murdering a pregnant woman to prevent her from revealing that he allegedly groomed her as a teenager and then staging her death as a suicide.

Former officer Matthew Farwell, 38, was charged Tuesday with fatally strangling Sandra Birchmore, 23, in her Canton, Mass., apartment in 2021. An initial autopsy wrongly ruled that Birchmore had killed herself after Farwell used his police knowledge to stage the scene of his alleged crime, prosecutors wrote in court documents.