Burning tyres poured smoke into the street outside Mariupol city hall hours after seven people were killed and dozens were wounded in continuing clashes in Ukraine.
A referendum on self-rule is due to be held in the eastern port city of Mariupol in two days, and threatens to provoke further unrest.
An eerie quiet fell over Mariupol as checkpoints became more vigilant following weeks of disruption from clashes between pro-Russians and Ukrainian forces.
European Union foreign ministers added 13 people to their visa ban and asset freeze list over Ukraine's crisis.
Well that’s the voting over, and no surprises so far. A ‘Yes’ vote claimed to be 89% in Donetsk, and suddenly Ukraine is no more.
Nearly 90 percent of voters in eastern Ukrainian region voted for self-rule, the head of the separatist election commission said.