With less than 48 hours to go until polling stations are due to open for Ukraine’s presidential election, the country’s restive Donbas region is edging the country ever closer to civil war. Today, at least a dozen people were reportedly killed across the region as fighting flared between pro-Russia rebels, far-right paramilitary groups, and soldiers.

The violence underscores the impossibility of holding an election in large pockets of Donbas, where a campaign of violence and intimidation is undermining the prospect of a fair and free election.

Gunfire in Karlovka village, just 15 miles south of Donetsk — the oblast’s administrative center — began at around 5AM this morning and lasted several hours, locals told VICE News. Grenade explosions were also heard.

Two shadowy groups have claimed responsibility for the attack on the rebel checkpoint at a bridge on the edge of the village. One, Donbas Battalion — a conglomeration of so-called “patriotic volunteers” — is rumored to be financed by the Kiev-appointed banking oligarch Ihor Kolomoisky. The other, Right Sector, is a nationalist group that rose to prominence during the Euromaidan protests, and has strong ties to neo-Nazi ideology.

Kolomoisky bank rolls another paramilitary group, Dnieper-1, which is licensed under Ukrainian law.

Violence has simmered across eastern Ukraine for more than a month since pro-Russia rebels began seizing buildings on April 6, but this is the first time nationalist paramilitary groups have openly admitted to launching assaults in the areas.

According to locals, the attacked checkpoint in Karlovka is normally only guarded by between 15 and 40 rebels. But the paramilitary groups’ offensive appears to have gone awry after the pro-Russia militia received a tip and called ahead for extra support.

One local told VICE News that he believed Chechen fighters, who are rumored to have been camped out in the area, were involved in the fight.

“We saw them moving through the woods two days ago when we were out on bicycles," 42-year-old Andrey tells us. "One lad approached them and they said they were Chechens here to help. I don’t know whose side they were on.”

Karlovka residents, who this morning found themselves in the midst of gunfire, were simultaneously afraid, angry, and confused.

“The gunfire seemed to die down and I tried to run to my grandmother’s house farther away, but I got caught in the crossfire,” one local told VICE News.

Many support the rebels. “I want to kill these faggot Nazi bastards, I would bury them,” says tattooed Valerey, dragging on a cigarette. “We used to be all together, but now we are not, now this is war." Leaning against the gate of the family home, his teenage grandson and friend proudly showed off a remnant of a rocket-propelled grenade launcher they found several feet from their house.

One of the enemies Valerey speaks of is not far away. Yegor, sprawled on the grass, is pale from loss of blood. He scrunches his face in agony as medics tend to his bullet wounds, one in each thigh. He tells VICE News that he is from Donetsk, and a member of the Donbas Battalion.

“Don’t leave, the separatists will come back, they will kill me,” he says, begging for a telephone to call his commander.

Three of his comrades were killed in front of him, Yegor says. Two by grenades, and the other gunned down when he tried to surrender to the rebels. By his side lies a bloodied black jacket with a Donbas unit’s name emblazoned across the back.

At least six people died in the attack, but it could not be verified which side the dead were on. The Donbas Battalion claimed heavy losses in the assault that they also admitted to initiating.

Eyewitnesses saw the rebels carting away at least four bodies in the back of a truck they hijacked from the Donbas Battalion. One of the corpses, which was shown to photographers at the scene, had a tattoo of a swastika.

Pro-Russia media and rebels have long said that nationalist and neo-Nazi groups operated in the region as provocateurs, a claim largely dismissed by western critics as Kremlin propaganda.

“We have come to take back Ukrainian land from the terrorists,” Denis Gordeyev, deputy commander of Dnipropetrovsk Right Sector unit, told VICE News.

Standing on the tarmac at a military checkpoint just 12 1/2 miles west of the fighting, alongside a motley crew of Ukrainian soldiers and Donbas Battalion fighters, the Right Sector fighter confirms what the pro-Russia camp has long alleged.

“We cooperate with the army and Donbas Battalion when we have common goals,” says Gordeyev, who denies Ukrainian soldiers were involved in today’s operation. “We move around a lot, so we are not stationed anywhere, but we are welcomed here [at the military checkpoint] and have been since the beginning.”

The burley blonde with singed eyebrows, who says he fought in this morning’s clashes, is dressed in civilian clothes — “Trust me, I’m a lawyer” is emblazoned on his t-shirt — but behind the deputy chief at least a dozen Right Sector members are dressed in military fatigues armed with automatic weapons, faces covered by balaclavas.

Despite the seemingly close relationship between Right Sector, Donbas Battalion and the Ukrainian military at the checkpoint, earlier in the day there were signs of tension when the Army did not come to the paramilitary group’s aid. Posting via Facebook, Semyon Semenchenko, the leader of the battalion, called the Army “motherfuckers” for not sending in APCs to rescue his forces.

"I have no idea why the Ukrainian military did not come to the rescue of its citizens," Goredeyev told VICE News.

Local law enforcement says there is little they can do to halt the violence, which has rapidly spiraled beyond their control. “This is our headache, what are we meant to do? We are not equipped to fight against this,” a senior figure in the district police said at the scene of the Karlovka clashes.

According to the police source, the squad under his command has not defected to the rebels, unlike many others in the region. The chief of police claims rebels have seized their guns.

“We did not so have so many guns, but in Horlivka [the rebels] have taken 400 and Slovyansk another 600,” he says. “It’s six of one, half a dozen of the other. You can’t trust either side anymore.”

Fighting also flared in other parts of the country's restive East today. In Luhansk there were reports of fighting between Ukrainian soldiers and local rebel forces known as the “southeast army.” Casualties have been reported on both sides but the number of dead is unconfirmed.

The people’s leader, Valeriy Bolotov, introduced martial law in rebel-controlled pockets of the oblast Thursday. The region is partitioned from north to south by the Ukrainian military, and a curfew has been in place since May 3.

Meanwhile another paramilitary force, the Lyashko Battalion, organized by nationalist Radical Party leader and presidential candidate Oleh Lyashko, killed two rebels and wounded at least one other after they stormed an occupied administrative building in Torez, 48 miles from Donetsk city.

Earlier this month, Lyashko released a clip on social media of him interrogating a rebel leader handcuffed and stripped to his underpants after Ukrainian forces attacked a building occupied by pro-Russia forces in the industrial port city Mariupol. Unarmed civilians were killed in the assault, which was also rumored to involve paramilitary groups.