A Russian military helicopter accidentally fired rockets near a crowd of spectators during military exercises in the west of the country, reportedly injuring two people.

Two videos of the incident show rockets slamming into the side of a small hill as onlookers watch an approaching pair of attack helicopters. Flames and debris erupted as people dived for cover.

In the footage two rockets are clearly visible streaking towards a military-type truck.

A clip apparently taken after the explosion showed more debris strewn around the vehicle.

The Moscow Times reported that two journalists were injured in the blast, and an unnamed military source was cited in a Russian news outlet as saying the firing occurred due to a technical glitch.

The online 66.ru portal said the accident happened on either Sunday or Monday at the Luzhsky range, 60 miles east of the Estonian border, during the Zapad-2017 drills, which have alarmed some of Russia's close neighbours.

A separate report, however, suggested there were three people injured, who were not civilians.

Russia’s government has denied it occurred during President Vladimir Putin's visit to the war games on Monday.

Zapad-2017 is Russia’s biggest military exercise in years. Some 13,000 soldiers, plus hundreds of tanks and other vehicles, are taking part in the joint Russian-Belarussian exercise.

The exercises began on Thursday across several firing ranges in both countries, and are due to run into Wednesday. As commander-in-chief of Russia’s armed forces, Mr Putin observed the simulated battles along with a number of top generals at the start of this week.

Two calls from The Independent to Russia’s defence ministry went unanswered.

The Russian Embassy in London passed on a link to a report by the RIA Novosti agency that said the ministry denied any such accident had taken place during the Zapad exercises on Monday.

“All messages on social networks about ‘volleys on a crowd of journalists’ and ‘a large number of seriously wounded’ are deliberate provocation or someone’s personal stupidity,” a spokesman for the western military district told RIA.

The videos in fact show “another incident happening earlier, when a truck was damaged”, the embassy said.