A Russian military helicopter mistook its target during a training exercise, leaving three people wounded on Sept. 16, according to reports. (Reuters)

The footage is striking: Two Russian helicopters swoop in low over a muddy field in the direction of a man walking past some civilian cars; a black plume rockets out from one of the aircraft; an explosion sounds, and smoke fills the screen. The next scene shows nothing but wreckage. 

Russian media reported Tuesday that three people were wounded in the incident, which reports described as an accidental launch of an air-to-surface missile in the direction of spectators at one of the sites of Russia’s Zapad-2017 military exercises.

The Russian defense ministry did not dispute the authenticity of  the video, which first appeared on a social media Tuesday and quickly spread to news reports. But the military, in the midst of war games designed to show off the military might and tactical precision of Russia’s reformed armed forces, dismissed the report of injured spectators as a “purposeful provocation or someone’s personal stupidity.”  In a statement,  it said that a helicopter had accidentally fired a rocket at an empty truck during a training exercise, but that no one was hurt. 

The Zapad, or “West,” exercises have featured an impressive show of forces as Russian and Belarusan military units simulate the response to an attack by an imaginary “Western Coalition.” The muscle-flexing, which began Thursday, highlights the scope of a fighting force that has taken a crash course of reforms and upgrades over the last decade.

The report of the misfired rocket came a day after President Vladi­mir Putin, dozens of international observers and more than 100 journalists took in an impressive 45-minute display of air and land firepower in a simulated battle at a firing range in northwestern Russia. That event went off without incident. 

On Sept. 18, President Vladimir Putin watched as the Russian military battled an imaginary Western invasion. (David Filipov,Joyce Lee/The Washington Post)

The state-owned NTV television station cited what it described as an official report detailing the incident involving an attack helicopter. The report said that the incident took place Saturday, that spectators were not seriously injured and that two cars were also damaged.

The report gave no other details on the civilians purported to be injured. Earlier, the news site 66.ru reported that two spectators were hospitalized with serious injuries after an inadvertent strike by a state-of-the-art Ka-52 helicopter.

The Defense Ministry denial cited Sept. 18, a different day than the claimed incident in the NTV report. The reason for the discrepancy was not immediately clear.

The military report cited by NTV said that on Sept. 16, a lieutenant colonel and a senior lieutenant carried out a sortie at 2:47 p.m. from an aerodrome to practice live-fire combat exercises.

Russia has invited NATO to attend events at the war games — at Monday’s exercise, a Post reporter saw observers from Germany, Italy, Croatia and Norway, all NATO countries. But NATO leaders have said that Russia is not being completely transparent about the war games, which they say may actually involve up to 100,000 troops.

Leaders of the Baltic nations that would be on NATO’s front line in a land war with Russia have said this year’s edition of Zapad appears to be a simulation of an attack against NATO forces in Eastern Europe. 

A photo provided by the Russian Defense Ministry shows a Russian soldier during a military exercise at a training ground near Kaliningrad, Russia, on Sept. 18, 2017. (AP)

Moscow has insisted that the exercises, which are held every four years, would rehearse a strictly defensive scenario and involve no more than 12,700 troops, just below the level that would require Russia to allow NATO observers under an international agreement.

Russia sees itself hemmed in by a hostile, expanding force in NATO. Putin has vowed to prevent revolutions in the former Soviet region similar to the 2014 rebellion that established a pro-Western government in Ukraine.