When police arrived at 35 Fernwood Ave. in Revere this afternoon, they found Lisa Bryson Roche, 42, with stab wounds, her son, Cory, 23, nearby with a knife. And when Cory Roche refused to drop his knife, an officer shot him, according to Suffolk County DA Dan Conley.

Cory Roche is expected to survive, Conley said at a press conference this evening. Late word is that he's been charged with murder and will be arraigned in the morning in Chelsea District Court.