There is no immediate explosion. The ordnance detonates approximately 18 seconds later, blowing up a section of the road, catching one of the cars as it passes and sending a parked car flying into the air before it lands on the supermarket roof.
Though embarrassing for the Russian military, the admission of "an accident" suggests that officials here do not believe the incident will negatively impact Russian public opinion of what the Kremlin still calls its "special military operation".