Fierce fighting erupts in the key town of Debaltseve in eastern Ukraine, despite a supposed ceasefire coming into effect last week.

International observers from the Organization for Security and Co-operation in Europe (OSCE) have been denied access to the town, which is a key transport hub in the region, by the rebels.

Both sides had been expected to begin withdrawing their heavy weapons from the town by Monday, but neither side met the agreed deadline.

The self-proclaimed Donetsk People’s Republic (DNR) had said that it did not believe that the ceasefire applied to Debaltseve, and had no plans to call off its campaign in the town, which rebels had surrounded by the time the ceasefire was announced.

The Ukrainian military claims to still be in control of the town, but the DNR claims to have taken control of most of the city, including the police and railways stations.

Elsewhere, the ceasefire has broadly held since it came into effect on Sunday.