DONETSK, Nov. 16 - Fresh volleys of artillery fire were heard across many parts of the separatist stronghold of Donetsk in eastern Ukraine on Sunday, a Ukrainian government statement said, after Kiev warned again of rebel preparations for a fresh offensive, Reuters reported.

Shelling from both sides has repeatedly punctured a ceasefire, agreed in a deal signed on Sept. 5 to end a war that has killed more than 4,000 people since April.