Pro-Russian rebels launched an offensive against the strategic port of Mariupol in eastern Ukraine on Saturday, prompting the European Union's foreign policy chief to warn of a further "grave deterioration" in EU-Russian relations.
Mariupol's city administration said the rebels had killed at least 30 people and injured 83 others by firing rockets from long-range GRAD missile systems.
The city of 500,000, on the Sea of Azov, is vital for eastern Ukraine's steel and grain exports and straddles the coastal route from the Russian border to Crimea, the Black Sea peninsula in southern Ukraine seized by Russia last March.