Russian helicopters taking part in that country's major week-long military exercises appear to have fired on civilians observing the display this week, sending two people to the hospital with serious injuries, according to reports.

A source told Russian news portal the missiles fired on their own due to a technical glitch.

"At least two cars burned down, two people were seriously injured, they are now hospitalized," the source said, according to a translation provided by Moscow Times. "The victims were most likely journalists."

Video of the incident was widely shared on social media.

The Russian Defense Ministry denied that the accident took place. "[A]ll social media messages about ‘rounds on a crowd of journalists,' ‘a large number of seriously wounded' are either a deliberate provocation or someone's personal stupidity.

"[Video footage] recorded an event that occurred at another time, when army aviation helicopter crews practiced ground attacks as part of a tactical exercise."

The major combined arms exercise, called Zapad 2017, is taking place Sept. 14-20 in western Russian and Belarus, prompting fears that Moscow is conducting a dress rehearsal for an invasion of Europe. Tens of thousands of Russian soldiers are taking part, along with gunships, warships, fighter aircraft, artillery and armored vehicles.

The incident reportedly took place near St. Petersburg at the Luzhsky range, where Russian President Vladimir Putin visited on Monday.