The BBC are reporting that a nurse has been killed at St George's in Hornchurch in Havering, Essex.
The Times has a little more detail:
Detectives launched a murder inquiry after the body of the victim, a white woman in her 30s, was found by members of staff in a garden behind St George’s Hospital in Suttons Lane, Hornchurch at 11am today. She had suffered multiple stab wounds. An ambulance attended - the hospital does not have an accident and emergency department - but the nurse was pronounced dead at the scene. Nobody has been arrested.