Twenty-six cases of coronavirus have been linked to a cardiology ward at Aberdeen Royal Infirmary.
Ward 109 at the hospital has been closed to new admissions and visiting because of the outbreak.
NHS Grampian confirmed an investigation is under way and care is being provided to patients as normal.
A health board spokesman said: “Following 26 detected cases of Covid-19 associated with Ward 109 at Aberdeen Royal Infirmary, the ward has been closed to new admissions and visiting.
“An Incident Management Team has been set up to investigate these cases.
“Care is being provided to patients on the ward as normal.”