Fierce fighting surges before cease-fire in Ukraine

ARTEMIVSK, Ukraine -- Fierce fighting surged Friday in eastern Ukraine as Russian-backed separatists mounted a major, sustained offensive to capture a strategic railway hub ahead of a weekend cease-fire deadline. At least 25 people were killed across the region, officials reported.

Clashes appeared only to have increased since a peace agreement was sealed Thursday in the Belarusian capital of Minsk by the leaders of Russia, Ukraine, Germany and France. German Chancellor Angela Merkel cautiously described the cease-fire that takes effect early Sunday deal as "a glimmer of hope."

But the pending cease-fire only appeared to spark a last-minute grab for territory that left at least 25 people dead. The government-held railway town of Debaltseve was on the receiving end of dozens of artillery and rocket salvos in the 24-hour period following the Minsk talks, Ukrainian military officials said.

CBS News correspondent Elizabeth Palmer reports that even with the cease-fire looming the Ukrainians are saying that more heavy armor has rolled across the border from Russia into Ukraine recently, including tanks and missile systems.

Military spokesman Andriy Lysenko said Friday that 11 soldiers were killed and 40 wounded over the previous day in eastern Ukraine. Regional authorities loyal to Kiev reported at least seven civilian deaths, while rebels said seven others were killed in artillery attacks on the separatist-held cities of Luhansk and Horlivka.

Associated Press reporters on Friday observed intense shelling along the highway north of Debaltseve, which remains the town's only land link with the rest of government-controlled territory.

The deadline for the warring sides to halt hostilities is Sunday morning, at one minute after midnight. Interfax-Ukraine news agency quoted Petro Mekhed, Ukraine's deputy defense minister, as saying that separatist forces had been given the task of hoisting their flags over Debaltseve, as well as the key port city of Mariupol, by Sunday.

Separatist forces recently have nearly completely encircled Ukrainian forces in Debaltseve, where all but a few thousand civilians have fled the fighting.

Ukraine says Debaltseve should remain in government control under the terms of a September peace deal. A copy of that agreement leaked to Ukrainian media shows the town lying on the government's side of the line of division agreed by rebel and Ukrainian officials alike.

But both Russian President Vladimir Putin and Ukrainian President Petro Poroshenko appeared to disagree Thursday on what the peace deal meant for Debaltseve.

Ukrainian access to the sole highway still linking the town to government-held territory looks to have compromised with the apparent capture of the village of Lohvynove, just north of Debaltseve. AP reporters on Friday saw the smoldering remains of two Ukrainian army trucks near the village of Luhanske, 6 miles up the road.

The Donbass Battalion, a unit with Ukraine's National Guard that is engaged in battles around Lohvynove, said in a statement that captured combatants had confirmed that Russian troops were actively involved in the battles.

Shells landed Friday as far as Artemivsk, a government-held town 25 miles behind the front line. Associated Press reporters saw the body of a child killed Friday afternoon after rocket fire hit a kindergarten there. It was not immediately clear who was responsible for the attack.

Moscow vehemently denies that it provides manpower and weapons to the rebel forces, but the sheer quantity of powerful weapons at the separatists' disposal has strained that position.

Russian state news agency RIA-Novosti quoted Kremlin spokesman Dmitry Peskov as saying Friday that Moscow would act only as a guarantor in the peace process, and could not affect developments on the ground.

"We simply cannot do this physically, because Russia is not a participant in this conflict," Peskov was quoted as saying.

Elsewhere, by the Azov Sea in southeastern Ukraine, government troops say they have clawed back a handful of villages. Troops there have denied reporters access to those operations, which aim to push rebel forces back away from the government-held Mariupol.

The cease-fire is to be monitored by the Organization for Security and Cooperation in Europe's observer mission in Ukraine. OSCE Secretary General Lamberto Zannier said in Kiev that he hoped hostilities would be halted by the deadline.

"We would really hope to see a decrease already between now and that moment," he said.

Zannier said that combatants would have to do more to enable the OSCE peace-monitoring mission, which makes ample use of drone cameras, to properly fulfil its mandate.

"Aerial vehicles have been targeted more than once, monitors have been taken hostage, so we need a change of attitude," he said.

The next step after the cease-fire is to form a sizeable buffer zone between Ukrainian forces and Russia-backed rebels. Each side is to pull heavy weaponry back from the front line, creating a zone roughly 30-85 miles wide, depending on the caliber of the weapons. The withdrawals are to begin starting Monday and be completed in two weeks.

Other thorny political questions, including a degree of autonomy for the disputed eastern regions, are to be settled by the end of the year.

The peace deal envisions an amnesty for people involved in the conflict, but the vague terms of that provision will likely be subjected to further disagreements. Speaking to parliament, Ukrainian Foreign Minister Pavlo Klimkin said amnesty would not be granted to anybody suspected of committing crimes against humanity.

"This is an absolute position that was unambiguously underlined during (Thursday's) negotiations," Klimkin said.