As fighting flares in eastern Ukraine, in breach of a fragile cease-fire, Ukraine accuses Russia of illegally sending a convoy into the country and planning to destroy the nation. (Reuters)

Their leaders back in Kiev may be offering peace. But here on the front lines, the battle-scarred patriots staring down pro-Russian rebels talk of giving Russian President Vladimir Putin just the opposite — a Ukrainian version of Chechnya’s guerrilla war.

“Every man in this battalion is ready to change tactics to liberate our homes,” said Apis, the nom de guerre of a 40-year-old division commander in Ukraine’s Azov Battalion, one of several paramilitary units fighting the separatists.

Staring out at the no man’s land dividing his ragtag group from the rebels, he added, “This peace will not last. Putin thinks he is a monarch, that we must all kneel before him. We will never kneel, but we can become guerrillas and send him body bags with Russian soldiers.”

Pro-Russian separatists first occupied government buildings, then solidified control of large swaths of territory in the east, sparking a bloody battle with Ukrainian forces that by mid-August had rebels on their back heels. Then, NATO and Kiev say, came an infusion of Russian support that almost immediately reversed the course of battle.

Now hopelessly outgunned, President Petro Poroshenko is seeking peace with the rebels — and, indirectly, Moscow — in a deal that could ultimately leave a swath of the east under Russia’s thumb. Yet in a country where partisans once fought bloody underground operations against occupying Nazis and, later, the Soviets, more and more voices here are insisting that Ukraine should instead endorse a protracted guerrilla war.

Such an effort, advocates say, could wear down an enemy that Ukraine cannot beat by conventional means. Poroshenko, while pursuing peace, conceded as much this week. He noted preparations were underway to launch counterinsurgency operations if the pro-Russian rebels completely break the current truce.

“The very idea that every meter of Ukrainian land will burn under the feet of invaders should become a factor restraining from large-scale invasion,” he said.

Still, the strength and success of such a movement is anything but assured. Any pro-Ukrainian guerrilla operation may fail to find popular support in the industrialized east, where a large segment of the population is genuinely pro-Russian and even more residents are simply weary of war. Also, fearing persecution, many pro-Ukrainians have already fled rebel-held quarters out east.

“It is not clear that the people in the east would support it,” said Mykola Malomuzh, former head of Ukraine’s foreign intelligence agency.

Nevertheless, advocates say a move toward sabotage, targeted assassinations and other insurgent tactics could potentially alter the dynamic of the conflict in the months ahead, costing the Russians perhaps more than they bargained for when launching their power play in Ukraine.

“Putin will choke on this peace,” said Igor Sutyagin, a Russian expert at the Royal United Services Institute in London. He predicted the rise of a sort of Chechnya lite in eastern Ukraine, calling it “a softer version of insurgent warfare.”

Yet attempts to start such operations so far have proven, at best, modestly effective. In June, for instance, two assassination attempts against a leader of the Donetsk People’s Republic — a major rebel organization — failed to kill their target, but did kill four of his assistants.

Ukrainian President Petro Poroshenko said on Friday there could be no military solution to his country's crisis and that the only way forward is through diplomacy. (Reuters)

Gathering calls for guerilla warfare could also pose a major problem for the Ukrainian government.

Demands for a counterinsurgency are growing particularly within Ukraine’s voluntary battalions created last spring to bolster national defenses. Effectively paramilitaries, they are populated mostly by amateur fighters — including many adhering to far-right ideologies. Several of them, when asked, expressed skepticism of Poroshenko’s peace plan.

Many have also begun to lose faith in the official command structure. In a recent bloodbath in the city of Ilovaysk, battalion members say they were ordered into a fight, then abandoned by the Ukrainian military.

If Kiev reaches a deal with rebels that they don’t support, paramilitary fighters say they could potentially strike pro-Russian targets on their own — or even turn on the government itself.

A 26-year-old battalion member at the front lines who goes by the name of Shmel said he was dispatched along with the rest of his unit to the horrific, multi-day battle in Ilovaysk, which began last month. Rebels claim to have killed, wounded or captured hundreds of pro-Ukrainian forces. Shmel said he personally watched two men in his unit die.

“They just threw us out there like red meat,” he said, rubbing his firearm as he spoke. With his home in the eastern Luhansk province still occupied by pro-Russian rebels, he said he and other paramilitary fighters would never agree to a plan that gives real power to the separatists after seeing so much bloodshed.

If Kiev strikes a deal they are not happy with, “believe me, we will not only fight the rebels, but will fight the government, too,” he said.

The debate over tactics here is shining a fresh spotlight on the paramilitaries, which have become something of a wild card in the conflict. Many of them — a hodgepodge of activists, professionals, blue-collar workers and wayward youths — have fought valiantly for their country.

But some units have also become a haven for far-right thought, and, like the rebels themselves, have been charged by Amnesty International with committing extortion, kidnapping and worse in the areas where they operate.

Hundreds of paramilitaries are now aiding in the defense of Mariupol — a vital port city where pro-Russian forces continue sporadic attacks on military positions despite the cease-fire. If ultimately overrun by separatists, Mariupol, experts say, may be the first real test of whether a pro-Ukrainian insurgency will find popular support.

In some quarters of the city, however, skepticism is running high. Gulnara, a 49-year-old woman with apparent pro-Russian leanings who was too afraid to give her last name, said her husband, a local restaurant owner, was kidnapped last week by men wearing black masks and camouflage.

“And since the Russians are not here, I can only guess it was them,” she said, referring to the volunteer battalions. “At this point, I don’t care if we are Russian or Ukrainian. We just want the fighting to stop.”

A former school here is now a training ground and barracks for the men of the Azov, who receive a $70 a month salary as well as minimal training and aging firearms from the government. One platoon leader, who called himself Kirt, conceded that the group’s far right views had attracted about two dozen foreign fighters from around Europe.

In one room, a recruit had emblazoned a swastika above his bed. But Kirt, a former hospitality worker, dismissed questions of ideology, saying that the volunteers — many of them still teenagers — embrace symbols and espouse extremist notions as part of some kind of “romantic” idea.

He insisted the group’s primary goal is defending its country against Russian aggression.

“It’s like 1924,” he said. “Putin is the new Stalin.”

Annie Gowen and Natalie Gryvnyak in Mariupol and Alex Ryabchyn in Kiev contributed to this report.