Navy midshipmen marched before the annual Army-Navy game in Philadelphia on Dec. 14. Photo: Matt Slocum/Associated Press

Cadets and midshipmen who flashed “OK” hand signs on national television during the annual Army-Navy football game on Dec. 14 didn’t intend to convey extremist messages, but were playing a game that involves the use of the gesture, according to findings of a military review released Friday.

The students likely will face punishment for unprofessional behavior for engaging in the game, but apparently were unaware that the hand sign they used has become associated in recent years with white-power extremism.

The redacted reports released Friday by officials at the U.S. Military Academy at West Point and the U.S. Naval Academy showed that, according to investigators, the cadets were behaving unprofessionally when they flashed the hand signs in the background of an ESPN segment on national television.

“We are confident the hand gestures used were not intended to be racist in any way. However, we are disappointed by the immature behavior,” said Naval Academy Superintendent Vice Adm. Sean Buck.

“Last Saturday I had reason to believe these actions were an innocent game and not linked to extremism, but we must take allegations such as these very seriously,” said West Point Superintendent Lt. Gen. Darryl Williams. “We are disappointed by the immature behavior of the cadets.”

The “OK” hand gesture has long been used in something called the “circle game.” In the game, when one person makes the hand sign, and a second person is caught looking at it, the second person gets punched. The hand sign is typically below the waist.

The same, seemingly innocuous hand sign took on added meaning around 2017, according to the Anti-Defamation League, when extremists began using it to connote support of white-power sentiments. One of the reasons extremists adopted the hand sign was because of its ambiguity.

The white-power hand sign isn’t typically flashed below waist level, but that connotation emerged when a man who is accused of killing dozens in mosque shootings in Christchurch, New Zealand, made the sign below his waist during a court appearance earlier this year.

Investigators recommended that service academy officials update training to ensure that cadets are aware of negative connotations of hand signs such as these and that such training remains current to take into account changes in the uses of hate group symbolism.

Write to Ben Kesling at benjamin.kesling@wsj.com

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