Secret information has been mistakenly published online by officials in at least three government departments, it has been revealed.
Confidential details about nuclear submarines were among the information accidentally posted on the internet.
Although the data was blacked out by Ministry of Defence workers, anyone who pasted the text into another document could read the 'redacted' data.
The file - which revealed how much structural damage would need to be caused to a sub's nuclear reactor before it went into meltdown - was hastily taken down after the mistake was pointed out.
But the blunders risk sparking a diplomatic row with the U.S., as the report - written in 2009 - revealed how American submarines deal with disasters.
Last night it emerged officials in the Department of Health and Department of Communities and Local Government have also failed to properly withhold confidential information when publishing documents under Freedom of Information laws.
The Ministry of Defence was today reviewing other documents to see if they had unwittingly put more secret data online.
A spokesperson blamed the information blunder on an 'admin error', but would not confirm whether disciplinary action is being taken against the official responsible.
Today the Daily Telegraph claimed further documents had not had confidential sections properly covered up.
Although a junior official will decide what data can be published and what must be withheld when a Freedom of Information request is received, the response must be signed off by a more senior officer before it is made public.
The nuclear submarine secrets were unwittingly published as part of a response to a FOI request.
Last night Conservative MP Patrick Mercer told the Daily Star: 'All our enemies are trying to get their hands on nuclear weapons and materials and any information in this document would be hugely interesting to them and potentially catastrophic.'
A spokesman for the Ministry of Defence said they reacted quickly when they realised nuclear submarine secrets had accidentally been published.
'As soon as we were told about this we took steps to ensure the document was removed. We take nuclear security very seriously,' he said.
The file had yesterday been taken off the site and replaced with a new secure version.
An MoD spokesperson said: 'We will be going through everything that is published and make sure everything has been redacted properly, then we will have to look through the procedures used.
'We will have to make sure everyone follows the same process.
'It was an admin error as the wrong programme was used during the redact period.
A spokesman for the Department of Communities and Local Government said: 'There are robust procedures in place to protect personal details in FOI answers. Any replies that do not conform to those procedures will be investigated.'
Confidential details about nuclear submarines were among the information accidentally posted on the internet.
Although the data was blacked out by Ministry of Defence workers, anyone who pasted the text into another document could read the 'redacted' data.
Submarine secrets: Ministry of Defence officials accidentally published confidential information about the risk of a nuclear sub going into meltdown in the event of an accident. Pictured is the nuclear sub HMS Tireless
But the blunders risk sparking a diplomatic row with the U.S., as the report - written in 2009 - revealed how American submarines deal with disasters.
Last night it emerged officials in the Department of Health and Department of Communities and Local Government have also failed to properly withhold confidential information when publishing documents under Freedom of Information laws.
The Ministry of Defence was today reviewing other documents to see if they had unwittingly put more secret data online.
A spokesperson blamed the information blunder on an 'admin error', but would not confirm whether disciplinary action is being taken against the official responsible.
Today the Daily Telegraph claimed further documents had not had confidential sections properly covered up.
- The Department for Communities and Local Government withheld details of commercial negotiations - but the secret information could easily be uncovered with ordinary software.
- The Department of Health blacked out names of people called to a private meeting about contaminated blood with a marker pen. However, when the documents were printed and held to the light the names could still be seen.
- In a further Ministry of Defence blunder, the names of people working on a military submarine project could be accessed.
Tory MP Patrick Mercer said the revelations are 'potentially catastrophic'
The nuclear submarine secrets were unwittingly published as part of a response to a FOI request.
Last night Conservative MP Patrick Mercer told the Daily Star: 'All our enemies are trying to get their hands on nuclear weapons and materials and any information in this document would be hugely interesting to them and potentially catastrophic.'
A spokesman for the Ministry of Defence said they reacted quickly when they realised nuclear submarine secrets had accidentally been published.
'As soon as we were told about this we took steps to ensure the document was removed. We take nuclear security very seriously,' he said.
The file had yesterday been taken off the site and replaced with a new secure version.
An MoD spokesperson said: 'We will be going through everything that is published and make sure everything has been redacted properly, then we will have to look through the procedures used.
'We will have to make sure everyone follows the same process.
'It was an admin error as the wrong programme was used during the redact period.
A spokesman for the Department of Communities and Local Government said: 'There are robust procedures in place to protect personal details in FOI answers. Any replies that do not conform to those procedures will be investigated.'