Ellington

LUHANSKE, Ukraine (AP) — Under a near-constant barrage of artillery fire, Ukrainian forces and separatist rebels fought Tuesday for control of the strategic railway hub of Debaltseve, a battle impeding implementation of a peace plan.

Ukraine denied rebel claims to have taken control of the town but acknowledged the insurgents had seized parts of it in heavy street fighting. The battle came despite a weekend cease-fire that obliged both sides to start moving back their big guns on Tuesday.

Debaltseve, a key railroad junction between the separatist east's two main cities, Donetsk and Luhansk, has been the focus of fighting over the past two weeks and capturing it would be a prize for the Russia-backed rebels.

The defense ministry said fierce street battles continued there Tuesday and government soldiers had been ambushed and taken prisoner, but gave no details on how many were seized. Rebel spokesman Eduard Basurin said hundreds of Ukrainian soldiers had surrendered in Debaltseve.

Associated Press journalists were turned back by Ukrainian forces well outside of Debaltseve and were unable to assess the status of the fight.

The leader of the self-proclaimed Donetsk People's Republic, one of two separatist entities, was wounded in the leg and hospitalized in the neighboring Luhansk region, Russia's RIA-Novosti news agency quoted a Luhansk rebel official as saying. Zakharchenko's life was not in danger, the report said.

The Ukrainian presidential office called on the European Union and NATO to condemn the Russia-backed rebels for violating the cease-fire brokered by the leaders of Ukraine, Russia, Germany and France last week.

The war in eastern Ukraine has already killed more than 5,600 people and displaced more than a million, the United Nations said Monday. It has also left the country's industrial heartland in ruins.

On Tuesday, a deadline passed for both sides to begin pulling back heavy weapons from the front line.

Rebel commander Vladimir Kononov said on Russian television that most of Debaltseve was under separatist control and urged the Ukrainian troops to surrender.

"Their only choice is to leave behind weaponry, lay down arms and surrender," he said.

The announcement by the rebels came after fierce fighting that appeared to be focused on Debaltseve. Both sides in the conflict claim the town is on their side of the cease-fire line, and the issue was not resolved under the cease-fire deal.

Rebel official Basurin announced in a televised briefing that the separatists "will take the initiative" and begin to pull back their big guns from some sections of the front line. He did not provide a timeline.

The Ukrainian government, however, insisted on a comprehensive cease-fire before pulling back its weaponry.

AP reporters saw near-constant artillery rounds fired Tuesday from Ukrainian government positions at rebel fighters around Debaltseve. Sustained shelling was heard in the area all morning, some coming from Grad rocket launchers.

"The situation in Debaltseve is extremely complicated and is changing by the hour," Ukrainian military spokesman Andruy Lysenko said late Tuesday. "Several groups of the enemy have burst into the city."

The cease-fire deal, which was to take effect early Sunday, specifies the pullout begin on the second day after the parties stop fighting. This condition has not been met, Lysenko said.

"As soon as the fire ceases ... we will be ready to begin the withdrawal," he said.

Fighting has stopped or subsided in some parts of war-torn eastern Ukraine, however. Basurin said Tuesday the separatists had not seen any violations of the cease-fire in the area around the rebel stronghold of Donetsk since 8 p.m. Monday.

The continued fighting comes as concern remains about whether the United States will decide to send lethal weapons to Ukraine.

Russian President Vladimir Putin said Tuesday at a news conference in the Hungarian capital, Budapest, that, "according to our information, these weapons are already being delivered." He did not elaborate but said the consequences of new weapons for Ukraine would be "the number of victims, of course, can increase. But the result will be the same as it is today. This is unavoidable."

He also suggested the Ukrainian forces in Debaltseve should lay down their arms.

"I reckon that the leaders of the fighters ... would not hold these people, prevent them from leaving the conflict zone and returning to their families," he said.

Rupert Colville, spokesman for the U.N. High Commissioner for Human Rights, told a briefing in Geneva on Tuesday that the U.N. was "alarmed" by reports of continued shelling and has not been able to get reliable information on casualties or the well-being of civilians.

"It is unclear how many civilians are still there," he said. "We are particularly concerned about the civilians trapped in the area. We believe there may be a few thousand hiding in cellars, struggling to get food, water and other basic necessities."

Elsewhere, at least one rebel leader claimed that his troops had begun to withdraw their heavy weapons.

"I was at the front line last night, and our tanks, our artillery were pulling back," Igor Plotnitsky, the leader of the self-proclaimed Luhansk People's Republic, northeast of Debaltseve, was quoted as saying by the Russian news agency Tass.

His claims could not be independently. However, Lysenko said Ukrainian troops "have not noticed any such actions" on the ground.