Poroshenko predicts 'large-scale hostilities' as Ukraine fighting intensifies

KIEV, Ukraine, June 4 (UPI) -- An increase in fighting in eastern Ukraine this week has provoked new fears that the delicate ceasefire will break down.

The Ukrainian government reported the deaths of five soldiers Wednesday in fighting near the town of Maryinka.

The separatist Donetsk People's Republic said 16 rebels and five civilians were killed. Both sides added there were numerous injuries. Observers with the Organization for Security and Cooperation in Europe (OSCE) suggested it was the separatists who initiated the fighting Wednesday.

The monitors said they observed considerable moving of separatists' heavy artillery in the hours before the fighting in Maryinka, regarded as among the most severe since the ceasefire, signed in February. The ceasefire has been broken numerous times, and the conflict between government troops and pro-Russian separatists has intensified this week. Russia has repeatedly denied sending troops or aiding the separatists.

Addressing Parliament Thursday, Ukrainian President Petro Poroshenko claimed a "colossal threat of the resumption of large-scale hostilities by Russian and terrorist forces," as well as a "full-scale invasion" by Russia. He added 9,000 Russian troops are currently in eastern Ukraine.