A computer virus has infected three London hospitals, which has reportedly shut down their computer systems for at least 24 hours.
The BBC reported that Sir Bartholomew's (Barts) in the City, the Royal London Hospital in Whitechapel and the London Chest Hospital in Bethnal Green, were forced to shut down their systems. The facilities make up St Bartholomew's and The London NHS Trust.
Manual back up systems were in use, with engineers still in the process of restoring computer systems. Operating theatres and outpatient departments were still operational during the incident, with non essential activities scaled back.
A&E remained open to walk in patients, but ambulances were being diverted to neighbouring hospitals in the short term.
According to Sophos expert Graham Cluley, the hospitals were infected by a variant of the Mytob worm. This spreads via email, planting a backdoor Trojan horse which can be used by hackers to gain access and control over a victim's computer.
The computer can then be spied upon to steal confidential information, to send spam, or to launch denial of service attacks.
He said: "There will, no doubt, be concerns that the confidentiality of patients' data may have been put at risk, and the hospital surely be keen to reassure the public that security has been maintained."
In a statement, the Trust said that well rehearsed emergency procedures had been activated to ensure that key clinical systems continued while network access was being established.
It said every effort was being made to provide transport for those that needed it, but services were likely to be disrupted to computer systems.
Patients with concerns about their appointment were told to contact the Trust on 0207 943 1335.
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