Pentagon press secretary George Little told reporters Tuesday that an official review of the book, "No Easy Day," determined that it reveals what he called "sensitive and classified" information. He was not more specific but said the book should have been submitted to the Pentagon before publication for a formal review of potential disclosures of such information.
A lawyer for the author, who uses the pseudonym Mark Owen, has disputed that he was legally obliged to have the book screened before publication.
Little would not say what damage may result from the book's revelations.
Little said the Pentagon has not taken steps to stop the book from being sold on military installations.
(Below, watch part of the interview Owen, who CBS Newswill not identify, gave to CBS' "60 Minutes." The full interview is scheduled to be broadcast Sunday.)
Pre-orders for the book have catapulted it to No. 1 on Amazon's best-seller list, displacing the erotic trilogy "Fifty Shades of Grey." An initial print run of 200,000 has been increased to 575,000 copies.
It was highly unlikely that the government would try to halt publication of the book itself, considering that a limited number of advance copies are already in the public domain and media reports have summarized the book's contents.
Previously, Little said Owen was in violation of two nondisclosure agreements that he signed in 2007 by failing to submit the book for an official security review before it was published. Owen's lawyer disputed this Friday, saying he believes the decorated former SEAL has "earned the right to tell his story."
Little would not say what legal options the Pentagon is considering or when it might take action.
Little suggested that the Pentagon might be satisfied if Owen were to stop the book's official release. The Pentagon obtained an advance copy last week, Little said.
"The onus is on the author," Little said, while declining to spell out what the author must do.
Robert D. Luskin of the law firm Patton Boggs wrote to Jeh Johnson, the Pentagon's top lawyer, on Friday informing him that his firm is representing Owen and asserting that he is not in breach of his nondisclosure agreements.
Luskin, who represented White House aide Karl Rove in the leak of CIA agent Valerie Plame's identity in the Bush administration, said the author had "sought legal advice about his responsibilities before agreeing to publish his book and scrupulously reviewed the work to ensure that it did not disclose any material that would breach his agreements or put his former comrades at risk. He remains confident that he has faithfully fulfilled his duty."
The Justice Department could go after the profits of the book in a civil proceeding. Department spokesman Dean Boyd declined any comment on the book Friday.
In the late 1970s, retired CIA agent Frank Snepp published a book about his CIA activities in South Vietnam without submitting it to the agency for prepublication review. The government sued to collect all profits and the court ruled in the government's favor. The government did not contend that Snepp's book contained any classified material.
In its 6-3 ruling in 1980, the Supreme Court said "undisputed evidence in this case shows that a CIA agent's violation of his obligation to submit writings about the agency for prepublication review impairs the CIA's ability to perform its statutory duties."
The government could consider bringing federal criminal charges against Owen. The potential charges and penalties would depend largely on what type of secrets were disclosed.