A Ministry of Justice spokesman said: "We treat the security of information very seriously and took immediate steps to recover the data as soon as the loss was reported to ensure that it went no further.
"These types of incidents are extremely rare but this does not mean that we are complacent.
"A thorough investigation was held by the prison who immediately altered their procedures, and further changes were implemented across the prison estate."
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From the time three bodies were found at a house in Oxfordshire to when prime murder suspect Jed Allen was found dead in woodland.
Mostly cloudy overnight, but as low pressure systems feed in as the week goes on an unsettled period can be expected.
The hunt for murder suspect Jed Allen has ended after police found his body two days after discovering his mother, stepdad and sister dead.