Theresa Riggi, 47
Theresa Riggi who killed her three children in her Scottish flat, has been found dead at Rampton Secure HospitalPA

A psychotic mother who stabbed her three children to death has been found dead at Rampton Secure Hospital.

Theresa Riggi was jailed for 16 years in April 2011 for killing her eight-year-old twins Austin and Luke and her five-year-old daughter Cecilia at their Edinburgh home in August 2010.

Rampton Secure Hospital in Nottinghamshire confirmed that an "unexpected death" of a patient had occurred but would not elaborate.

Reports indicated that it was US-born Riggi.

Riggi, 49, who admitted murder on the grounds of diminished responsibility, had been held in Cornton Vale Prison in Stirling, Scotland, before she was transferred to Rampton for secure psychiatric care.

The move came two years after she was allegedly disfigured for life by a fellow inmate at Cornton Vale.