The cyber attack on the NHS is thought to be lead by Russian group.

The attack on lab service provider Synnovis has impacted the delivery of services at Guy's and St Thomas', King's College Hospital NHS Foundation Trusts and primary care services in south east London.

Guy’s and St Thomas’ trust (GSTT) has gone back to using paper, rather than computers, to receive the outcome of patients’ blood tests.

The attack on Monday (4 June) has also forced seven London hospitals to cancel an undisclosed amount of operations, blood tests and blood transfusions.

Additionally, The Guardian reported that the hack has also affected the South London and the Maudsley (Slam) trust, England’s largest provider of mental health services.

The NHS said in a statement: “Emergency care continues to be available, so patients should access services in the normal way by dialling 999 in an emergency and otherwise using 111, and patients should continue to attend appointments unless they are told otherwise. We will continue to provide updates for local patients and the public about the impact on services and how they can continue to get the care they need."