Russian-backed separatist authorities in eastern Ukraine said on Friday that a parked jeep with nobody inside had been blown up near a government building in the centre of the city of Donetsk.
A news outlet for the self-proclaimed Donetsk People's Republic urged residents to remain calm and not to move around the city if possible.
Nobody was reported to have been hurt in the explosion.
A Reuters witness said the jeep had been completely torn apart.
