At least four people have been shot dead in continued fighting between people backing Kyiv and pro-Russian activists in Odessa, police sources say.

The trade union building in the city fire was set on fire, according to regional police.

At least 38 anti-government activists reportedly became trapped inside the building and have died from smoke inhalation.

It’s some of the worst violence in the mainly Russian-speaking Black Sea port since Ukrainian President Viktor Yanukovych was ousted in February.

Odessa is close to Crimea, which was annexed by Moscow in March.