April 9, 2009 -- A top British counter-terrorism official has resigned after he was photographed yesterday carrying a top secret document regarding an ongoing investigation into suspected al Qaeda "driven attack planning within the UK" in plain view. The embarrassing blunder caused an uproar in England, and authorities rushed to arrest 12 men under the Terrorism Act in the now compromised terrorism investigation.

In a statement, the assistant commissioner at the center of the scandal, Bob Quick, acknowledged that he may have compromised the operation, adding, "I deeply regret the disruption caused to colleagues undertaking the operation and remain grateful for the way in which they adapted quickly and professionally to a revised timescale."

Sources tell ABC News the planned large-scale attack was imminent, with definite ties to al Qaeda.

The Daily Mail reported that Quick was resigning with a pension of over $110,000 British pounds (over $160,000).

The BBC and other British news outlets had published photographs of Quick as he was heading to a meeting at 10 Downing Street, in which he can be seen carrying a document labeled "Secret" and which contained details about an upcoming terrorist operation.

British Raids Result in 12 Arrests

Several hundred officers were involved in raids resulting in the arrests of the 12 men, who ranged in age from a teenager to a 41-year-old man, according to the Greater Manchester Police, who were also conducting searches at eight locations. Eleven of the men arrested were Pakistani-born nationals in Britain on student visas, while the other was from the UK.

"Although the operation is ongoing, this phase is still in its very early stages, so the information we can release about it is limited," said Detective Chief Superintendent Tony Porter, head of the North West CTU.

According to the British newspaper "The Telegraph" the exposed "briefing note" contained details of the locations and manner of the intended arrests, names of senior officers in charge of the operation and the "media strategy" once the suspects were rounded up.

Scotland Yard Official Regrets Mistake

British defense press officials sent an urgent note to all major British media alerting them " a media agency may be offering a photograph which contains highly sensitive information about a current counter-terrorist operation" and urging them not to publish details of the operation without seeking "advice", but the damage was done.

A Scotland Yard spokesman later told reporters the top counter terrorism official had apologized to his colleagues.

"Assistant Commissioner Quick accepts he made a mistake on leaving a sensitive document in open view and deeply regrets it."

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