Updated

An academic review board at the United States Army War College Thursday formally notified the office of a Montana senator running for re-election that it would review a report he plagiarized passages in a graduate paper, Fox News has learned.

Fox was told possible consequences for Sen. John Walsh, if the report was found to be true, could include revocation of his master’s degree.

Walsh suggested Wednesday that medication he took for post-traumatic stress disorder after service in Iraq may have been responsible for apparently plagiarized passages.

His office told Fox it would cooperate with the War College inquiry.

Earlier, it released a statement saying, “Senator Walsh included 96 citations for a 14-page paper at the U.S. Army War College in Carlisle, Pennsylvania. He acknowledges the citations were not all done correctly, but that it was an unintentional mistake.”

It also claimed the paper was not a thesis, as had been reported earlier.

"I don't want to blame my mistake on PTSD, but I do want to say it may have been a factor," Walsh told The Associated Press. "My head was not in a place very conducive to a classroom and an academic environment."

The senator is running against Republican Rep. Steve Daines to keep the seat Walsh was appointed to in February when Max Baucus resigned to become U.S. ambassador to China.

The apparent plagiarism in Walsh's 2007 paper, titled "The Case for Democracy as a Long Term National Strategy," was first reported by The New York Times in a story posted online Wednesday afternoon. Walsh submitted the paper to earn his Master of Strategic Studies degree nearly two years after he returned from Iraq and about a year before he became Montana's adjutant general overseeing the state's National Guard and Department of Military Affairs.

The paper, reviewed by the AP after the Times posted its story and graphics online, includes a series of unattributed passages taken from the writings of other scholars.

Fox News’ Chad Pergram and The Associated Press contributed to this story