WASHINGTON (AFP) - A sergeant at the US West Point military academy has been accused of secretly filming female cadets without their consent, including when they were in the shower, officials said Wednesday.

The allegations at the prestigious institution mark the latest embarrassment for a force dogged by sexual assault and harassment cases.

Sergeant First Class Michael McClendon has been charged under the military's legal code with indecent acts, dereliction of duty, cruelty and maltreatment and acts harmful to good order and discipline, according to a US Army statement.

McClendon, who served two combat tours in Iraq and received a Bronze Star, had been overseeing a company of 125 cadets at the military academy, said a defence official, confirming details first reported by the New York Times.

The case had been under investigation since May 2012, said the official, who spoke on condition of anonymity.

"We take this seriously and have offered the victims appropriate support services," the official said.

The allegations came to light days before Defence Secretary Chuck Hagel was due to deliver a commencement address at the academy this weekend.

Mr Hagel "was briefed this morning and disturbed by the allegations," another defence official said.

The accused sergeant had been assigned to West Point from July 2009 through May 2013 but has been relocated to Fort Drum in New York state pending the outcome of the investigation.

The case is the latest in a wave of high-profile sexual assault incidents in the ranks, prompting outrage and calls for new legislation.

A Pentagon report issued this month showed a sharp rise in reports of "unwanted sexual contact" over the past two years, with prevention efforts so far failing to stem the tide.

The head of the Air Force's sexual assault prevention programme was arrested this month on charges he groped a woman in a parking lot. And an army soldier who worked in a rape prevention programme in Texas is under investigation for alleged sexual assault and forcing one of his subordinates into prostitution.

President Barack Obama has voiced disgust and vowed to get the problem under control.

The alleged electronic voyeurism at West Point, if confirmed, threatens to aggravate the military's image problem with potential female recruits, amid negative publicity over the spike in sexual assaults.

But the vice-chief of the US Army, General John Campbell, said the military was determined to safeguard its soldiers and to act swiftly when allegations arise.