Ukrainian forces have entered the pro-Russian separatist stronghold of Sloviansk in the east.

President Poroshenko has ordered the military to hoist the Ukrainian flag over the city council building.

The extent of Ukrainian forces' control over the town remains unclear, but some reports quoted separatists as saying they were evacuating.

Ukrainian forces launched an offensive against the separatists this week after a 10-day ceasefire broke down.

Interior Minister Arsen Avakov said on Facebook that a large number of insurgents had left Sloviansk.

He said the rebels were "suffering losses and surrendering" after being met by Ukrainian forces.

Mr Avakov said "some intelligence suggests" that the military commander of the self-declared Donetsk Peoples' Republic (DPR), Igor Strelkov, was among those leaving, but this has not been confirmed.