STAMFORD, Conn. (AP) A 76-year-old Stamford woman who police say was severely beaten by her son has died.

Maryann Anderson died Thursday after being hospitalized three days. Doctors removed part of her skull to reduce swelling of her brain.

Her son, 42-year-old Timothy Anderson, has been charged with first- and third-degree assault, unlawful restraint and disorderly conduct. He's being held on $500,000 bail.

It was not known Friday if he's represented by a lawyer.

Police say manslaughter or murder charges could be filed against Anderson, depending on autopsy results and the investigation.

Police say he went into a rage Monday after being confronted by his mother and brother about his failure to take medication for psychological problems. Police say he grabbed his mother's collar and repeatedly punched her in the face.