US patient slain in hospital by her son

A woman who was in an intensive care unit of a US hospital has been shot dead by her son.

A patient has been shot dead inside an intensive care unit by her son, leading to a lockdown at New Hampshire's largest hospital, authorities say.

Authorities said Travis Frank, 49, of Warwick, Rhode Island, was arrested and will be arraigned on Wednesday on first-degree murder charges for the shooting shortly before 3pm on Tuesday at Dartmouth-Hitchcock Medical Center in Lebanon.

Attorney General Gordon MacDonald identified the victim as Frank's 70-year-old mother, Pamela Ferriere, of Groton, New Hampshire.

No possible motive for the shooting was released.