Killer of 23-Year-Old Sandra Birchmore Was Cop Wearing A Mask: Prosecutors

A Massachusetts apartment building's security camera captured the haunting final images of 23-year-old Sandra Birchmore. Prosecutors say four hours later, an individual in a mask and a hoodie appeared in the lobby, and Birchmore was never seen again. Prosecutors say the masked individual was actually a police officer named Matthew Farrell, and are accusing him of Birchmore's murder. Farrell has pleaded not guilty. His attorneys say that Birchmore committed suicide.