Cambridge University Hospitals is experiencing a second day of serious computer problems and is diverting ambulances to other hospitals and asking the public to avoid A&E.
Peterborough City Hospital is also reporting its Emergency Department is incredibly busy today, Tuesday March 6.
A statement from CUH this afternoon said: "Cambridge University Hospitals is currently experiencing significant issues with its computer network systems.
"As always, patient safety remains our top priority and ambulances are diverting to alternative regional hospitals.
"The public is asked not to attend A&E unless absolutely necessary. Call NHS 111 for advice, 999 in an emergency.
"Technical experts are working to resolve the problem as soon as possible and staff are working to a well-versed business continuity plan.
"Although emergency surgery continues, elective operations have been cancelled. Outpatients should assume that appointments are going ahead unless advised otherwise by the hospital."
Peterborough City Hospital added: "We are heading into this afternoon with an very busy ED, there are alternative options which you choose from. The Minor Illness and Injury Unit on Thorpe Road is open until 8pm, alternatively you could visit a pharmacist, the GP Hub or call 111 for advice."