WASHINGTON — The Pentagon said on Monday a publisher has destroyed nearly 10,000 copies of a spy memoir by a former army officer in Afghanistan after officials charged it exposed US military secrets.

With Pentagon representatives looking on, St. Martin's Press pulped the first print run of "Operation Dark Heart" a week ago and has released a revised version in a deal with the US government.

"There were approximately 9,500 copies of the book that contained classified information that the department entered into an agreement with the publisher to destroy," Pentagon spokesman Colonel Dave Lapan told reporters.

"The publisher conducted that destruction a week ago on Monday the 20th, with DoD (Department of Defense) observers there to witness it."

The US government, in an unusual move, reimbursed the publisher for the cost of the first printing as military officials had initially approved the manuscript for publication.

The pulped books were sent for recycling but it remained unclear how many electronic versions of the first edition were still circulating, as reviewers had been sent copies of the memoir.

"There's no way of telling how many electronic versions of the book that might be out there," Lapan said.

In the memoir, titled "Operation Dark Heart: Spycraft and Special Ops on the Frontlines of Afghanistan -- and the Path to Victory," the author, Anthony Shaffer, a lieutenant colonel in the army reserve and former Defense Intelligence Agency officer, recounts his five-month stint in Afghanistan in 2003.

The text of the latest edition was altered where agreement could be reached and when the two sides disagreed, the disputed text is blacked out, the Shaffer's lawyer told AFP earlier this month.

The author, who was decorated for his service in Afghanistan, condemned the Pentagon's move, saying he had taken care not to reveal classified information.

"The whole premise smacks of retaliation. Someone buying 10,000 books to suppress a story in this digital age is ludicrous," he told CNN television.

The dispute over the book underscores a tough line by President Barack Obama's administration over alleged leaks of sensitive information, with authorities pursuing several prosecutions.

The book's title reportedly refers to the name of a 2003 plan to go after several operational bases used by Afghan Taliban insurgents in neighboring Pakistan.

But because the operation would have required attacking the Taliban in Pakistan, the plan was called off, a decision that angered the author.

The book's release comes as Pakistan issued a strong protest Monday over strikes last week by NATO helicopters on Pakistani territory near the Afghan border.

But the alliance-led force defended its operations, saying foreign troops had the right to defend themselves.