Washington (CNN) -- The Pentagon general counsel threatened legal action Thursday against a former Navy SEAL who wrote a revealing book about last year's Osama bin Laden raid, warning him he has violated secrecy agreements and broken federal law. In a letter addressed to "Mark Owen," the pen name of book author Matt Bissonnette, General Counsel Jeh Charles Johnson wrote the Pentagon is considering pursuing "all remedies legally available" against the former SEAL and his publisher, Penguin Putnam. "In the judgment of the Department of Defense, you are in material breach and violation of the nondisclosure agreements you signed. Further public dissemination of your book will aggravate your breach and violation of your agreements," Johnson wrote.
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NEW: The Pentagon threatens legal action against the author
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NEW: It says Matt Bissonnette has violated secrecy agreements he signed
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Bissonnette says he was one of the SEALs who finished off bin Laden
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Bissonnette was a chief petty officer when he left the Navy
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