The 173rd Airborne Brigade is investigating what went wrong during an airborne drop that resulted in three Humvees free-falling to their destruction, as depicted in a widely-shared online video.

On April 11, the Army conducted a heavy drop and personnel airborne operation as part of exercise Saber Junction 16 at Hohenfels training area in Germany. About 150 supply bundles, vehicles, communications equipment and indirect weapons systems were dropped, according to Army spokesman Maj. Juan Martinez. But three Humvees slipped from their rigging as their parachutes deployed. plummeting hundreds of feet to the earth. Martinez said no one was hurt.

"The specific malfunctions that occurred on this day are under investigation," Martinez said in an email to Army Times. "There were multiple rehearsals and inspections of the equipment prior to mission execution. We cannot speculate on what went wrong until the investigation is complete."

Martinez also hinted at the severity of the issue, writing in a subsequent email that "this investigation will receive the highest priority."

The video, viewed more than 1 million times since U.S. Army W.T.F! moments posted it to Facebook, shows a couple of planes pass and drop their cargo without incident. The third plane's first item, one of the ill-fated vehicles, has it's parachute deploy initially. But a few seconds after it leaves the aircraft, it slips free and falls off its platform.

Humvee mishap during airborne operation

During an April 11, 2016, airborne operation by the 173rd Airborne Brigade Combat Team, three Humvees slipped from their parachute rigging and plummeted to earth. The Army is investigating what went wrong.

Someone standing near the camera seems to instantly recognize what is happening, yelling "Ooo, Yeah! Yes!" as it slips. The person in the video laughs as the free-falling Humvee crashes into the ground and kicks up a cloud of smoke. About 30 seconds after the first impact, the second vehicle slips free of its platform and rigging and plummets as well.

After more laughing, the voice says "called it!" around the time that the third vehicle slips free off camera, which moves to capture the descent and crash. Eventually a person in the group watching notes of one of the crashed vehicles "it's on fire" and asks, "Do we need to call that up?" just before the video ends.

Pictures purportedly of the carnage in the aftermath, were also posted on Twitter.

"While (the commanders of the 173rd) are aware of the video, it does not overshadow the hard work of the paratroopers, allies, and partners that took place during Saber Junction 16," Martinez said.

He said the Army does not know who shot the video nor their role in the exercise: "(Joint Multinational Training Command) is conducting (an investigation) to identify the person who shot the video. As far as disciplinary actions are concerned, nothing has been decided."

Saber Junction 16 is an exercise running from March 31 to April 24, involving about 5,000 soldiers from 16 allied European partner nations. It's stated goal is to evaluate the readiness of the 173rd to conduct unified land operations (a simultaneous combination of offensive, defensive and stability missions), with an emphasis on tactical interoperability. It's conducted annually with one of the two Army brigades in Europe.