Computer systems in numerous hospitals across Northern Ireland were hit by a virus today.
A "large number" of the 19 Health Trusts in the North - including that of the major Royal Victoria Hospital in Belfast - were affected by the virus which disrupted their systems and networks, said a Department of Health spokesman.
The virus caused problems by generating spurious network traffic, he said.
The affected trusts were isolated from the health and social services network while steps were taken to remove the virus.
The number of systems affected was reduced as they were swept to remove the virus, the spokesman said.
He added that contingency plans in place in the trusts should ensure disruption was kept to a minimum.
An investigation was launched to see how the computer virus got into the system and where it came from.
PA