Ukraine's army on Wednesday accused pro-Russian forces of launching a big new attack against government positions in breach of a shaky ceasefire deal. Rebel forces began a "large-scale offensive against Ukrainian positions" close to the pro-Russian separatist stronghold of Donetsk using some dozen tanks and up to a thousand troops, Ukraine's General Staff said in statement, adding that government troops had fought back the attack using heavy artillery. More civilian deaths and a new and unusually intense round of fighting Wednesday in eastern Ukraine are rekindling fears that a shaky cease-fire deal reached in February may be teetering toward collapse.