Not guilty plea in family's killing

Woburn, Mass. (AP) - A Winchester man accused of killing his wife, two children and mother-in-law has pleaded not guilty to four counts of first-degree murder.

Thomas Mortimer IV was arraigned in Woburn Superior Court Thursday following his indictment last week. He has been held without bail since his arrest after the killings in June.

Mortimer frowned as he entered pleas of not guilty in the slayings of 41-year-old Laura Stone Mortimer, 64-year-old Ellen Stone, 4-year-old Thomas Mortimer V, and 2-year-old Charlotte Mortimer.

The family was found beaten and stabbed to death in their Winchester home.

Prosecutors said Mortimer wrote two letters on his computer confessing. Authorities said Mortimer killed his family after an argument with his wife.

His lawyer has said he has mental health issues.