Several reported dead as Ukrainian forces clash with separatists in Mariupol

Heavy gunfire rang out in the eastern Ukrainian city of Mariupol on Friday amid heavy clashes between government forces and pro-Russian separatists.

Ukraine’s Interior Minister Arsen Avakov announced the killing by security forces of some 20 pro-Russian militants after they allegedly tried to seize control

of police headquarters in the city.

At one point, the targeted police building caught fire.

A police commander was killed; allegedly by a sniper. A number of people were reportedly wounded.

If independently confirmed, the death toll would be among the heaviest inflicted on the rebels during fighting in the east.

Referring to the separatists as 'terrorists,' Avakov said their attempt to take control of the building had turned into a battle.

The insurgents are said to have fled once the police headquarters caught fire. Ukrainian forces reportedly left the city shortly afterwards.

Kyiv claims the separatists are backed by Moscow and are receiving additional support from Russian special forces on the ground. Russia, meanwhile, denies any involvement.

The assault came on the back of Russian President Vladimir Putin’s first visit to Crimea since the region’s annexation in March.

International attempts to prevent Ukraine from sliding into civil war are ongoing.