Betsi Cadwaladr Health Board has closed a mental health unit after concerns were raised about the quality and safety of patient care.
Tawel Fan mental health ward in the Ablett Unit at Ysbyty Glan Clwyd will close with immediate effect on a temporary basis while an investigation is undertaken.
The health board says it's working with local authorities and the police.
The Welsh Government and Health Inspectorate Wales have also been informed.
A small number of staff have been removed from clinical duties while the investigation takes place.
The health board says the remaining staff will be redeployed to support patients in other clinical areas.
The health board says alternative arrangements have been made for the small number of patients affected to be cared for elsewhere.
Wrexham Maelor Hospital has suspended admission to three wards following an outbreak of norovirus.
It comes after 11 patients showed symptoms in the last 48 hours.
Betsi Cadwaladr University Health Board says it has put in place extra measures to tackle the outbreak.
Seven patients who suffered from the C difficile infection in North Wales have died, during September and October.
There were 47 cases reported in October:
- 4 at Wrexham
- 12 at Glan Clwyd
- 11 at Ysbyty Gwynedd
- 20 at non-acute sites
Betsi Cadwaladr University Health Board say they're working with Public Health Wales to understand all of the issues surrounding infection control and any issues that need addressing.
The Public Services Ombudsman has ordered one of Wales leading hospitals to pay £5,000 compensation to the family of a 30-year-old Rhyl man who died, needlessly, from liver disease.
Carl Nolan was born with cirrosis of the liver and diagnosed with the condition a decade before he died - but no-one told him of the findings until it was too late.
Today Wales' medical ombudsman ruled that Carl's death was wholly avoidable.
Peter Tyndall, The Public Services Ombudsman for Wales says Carl Nolan could have had a liver transplant had his liver disease been diagnosed earlier.
A north Wales health board says the treatment given to Carl Nolan, who died of liver disease at the age of 30, was not up to scratch:
We have received the Ombudsman's report and accept its findings in full. The health board recognises that some of the care given was below the standard that should have been provided to the patient and family.
We fully accept the recommendations in the report and have taken action to address each one made. We are reviewing our appointment system and process, and gastroenterology care pathways to provide an improved and more robust safe service for patients.
We are also making sure that safeguard measures are implemented to improve our standards of engagement with patients while they are treated by the health service in North Wales.
A man who was born with liver disease died at the age of 30 following a catalogue of errors by his local health board which - ultimately - prevented him from having a transplant.
Unbeknown to him Carl Nolan had cirrhosis - a life threatening condition - but when he became ill and visited Glan Clwyd Hospital in Bodelwddyn, Denbighshire, staff failed to tell him about his complaint and he went without any medical treatment for several years.
Eventually when his liver was failing Mr Nolan was admitted to hospital but died three days later.
In a report published today the Public Services Ombudsman for Wales says: "Had he been treated three days earlier, Mr Nolan should have recovered from the infection and had a chance of receiving a liver transplant. This opportunity to survive and flourish was denied to him."
Betsi Cadwaladr Health Board has agreed to write to Mr Nolan's family to acknowledge its failings and pay them £5,500.
North Wales' health board says the healthcare professional infected with Hepatitis C worked briefly at Wrexham Maelor Hospital (known then as the Maelor General Hospital) in May and June 1978.
Betsi Cadwaladr University Health Board says the risk of passing on the virus during a healthcare procedure is low, and could only happen if the worker suffered an injury causing them to bleed while treating the patient.
It says it has been reviewing its records, and obstetric and gynaecology patients from that time have been offered advice a blood test as a precautionary measure. Specialist clinic sessions will be held at Wrexham Maelor Hospital.
Andrew Jones, Director of Public Health for the Betsi Cadwaladr University Health Board, said: “I know that this news will cause some concern for patients who were seen in Wrexham at around that time. However I want to stress that the risk of transmission is low."
"Even so, it is important that we contact patients who were treated by this person and offer them support and the opportunity of a blood test. This will allow us to give reassurance that all is well or, if we do identify a person who is carrying the virus, ensure they get advice and treatment."
A hospital board which has had the highest MRSA and C.diff infection rates in Wales over the past year says it needs to improve the way it tackles the problem.
The admission by Betsi Cadwaladr University Health Board in North Wales comes after a critical report on an outbreak earlier this year.
Betsi Cadwaladr University Health Board said Prof Duerden's report confirms that it "must do more to improve infection prevention and control".
It focuses on improved leadership and management, and also the way cases are reported to the board and to the Welsh Government.
First we must apologise to the people of North Wales that our infection control practices have not been as good as they should have been. This has again been made clear in Professor Duerden's important and helpful report and we are acting quickly to make sure that the shortcomings that he has identified are addressed.
We have made it clear that we have an attitude of 'zero-tolerance' to preventable infection across the organisation. As an immediate step I have brought in a leading expert in infection prevention to work with us in North Wales as we improve our wider infection control services.
We have also put in place a weekly monitoring system at board level and we now have infection control groups led by senior clinical staff in each acute hospital to make sure there are clear lines of reporting and accountability at a local level. We are also in the process of recruiting additional nurses to our infection control teams.
I hope that by commissioning and publishing this report, and acting on its findings, we will be able to demonstrate and assure patients of the Health Board's determination to make the necessary and urgent improvements.