A hand grenade apparently exploded on the pitch during a derby football match in Iran.

Iranian television showed one of the players apparently pick the live explosive up, thinking it was a piece of harmless debris.

The unverified footage then shows him nonchalantly tossing the grenade over the touchline.

Moments later it blows in a plume of smoke and flame, sending referees and players from both sides in all directions as they run for safety.

Incredibly, nobody was hurt in the blast but the game was cancelled and the police have apparently launched an investigation.

The game is understood to have been in the central Iranian city of Isfahan, hosted by Foolad Sepahan - one of the country's top teams.