SLOVYANSK, Ukraine — A shootout at a checkpoint run by pro-Russian militants near the town of Slovyansk that left at least three people dead Sunday highlighted that a truce reached days earlier by diplomats in Geneva was fraying in eastern Ukraine.
At around 2 a.m. on a road lined with blossoming apricot trees, four cars drove toward the checkpoint and their occupants opened fire, killing three local men who were standing guard, according to pro-Russian militants who control this town.
“We thought nothing would happen because it was the holy night,” said Yevgeny Bondarenko, 62, who said he had been there to celebrate Easter with the people at the checkpoint. “Who can we trust now?”
It was unclear whether the shooting was an event staged by provocateurs, an accident or an attack on pro-Russian militants. The difficulty in sorting out what happened will resonate far beyond Slovyansk, the linchpin of a string of midsize towns north of the regional capital, Donetsk, that are controlled by pro-Russian militants.
A diplomatic settlement reached Thursday by the European Union, Russia, Ukraine and the United States called for illegally armed groups to lay down their weapons, though the chances of this formula for peace succeeding seemed slim from the beginning.
Within hours, pro-Russian militants in eastern Ukraine said they had no intention of disarming in accordance with the agreement, which they did not sign. Russia’s Foreign Ministry said the provision calling for disarmament covered “in the first place” the Ukrainian nationalist group Right Sector, which has its base in western Ukraine.
The United States has said it will impose additional sanctions on Russian businessmen, and possibly on a bank or oil company, if the Geneva agreement falls apart. So far, militants have not budged from the buildings they have occupied or handed in their guns.
Ukraine’s Foreign Ministry issued a statement Sunday calling groundless the Russian ministry’s assertion that the attackers had been members of Right Sector. Right Sector also denied any involvement.
“The Russian side must be reminded about their obligations under the Geneva agreement to bring all necessary influence to bear on separatists to clear illegally held buildings, unblock roads, lay down arms and prevent any bloodshed,” the Ukrainian statement said.
Life News, a Russian tabloid television channel, reported that the defenders of the town had found a business card of the leader of Right Sector, Dmytro Yarosh, in the belongings said to have been left behind by one of the attackers, along with stacks of dollars and guns.
The Russian Foreign Ministry issued a statement saying that “as a result of an attack by insurgents of the so-called Right Sector, innocent civilians have died.” It added that pro-Russian fighters had found “aerial photographs of that district” and Right Sector emblems in cars seized from the attackers. “The Russian side is indignant at this provocation of the insurgents, which shows the Kiev authorities’ unwillingness to rein and disarm the nationalists and extremists,” it said.
The authorities in Kiev, Ukraine’s capital, ridiculed and rejected the Russian statement.
The checkpoint was a confused scene after the shootout. The remains of a pickup truck and a sport utility vehicle sat in the center of the road, incinerated except for two unburned out-of-town license plates: one screwed onto a fender, the other merely set on a fender.
Bullet holes in the pickup truck’s driver-side door showed that the truck had been fired on from the side or from behind as it faced the checkpoint that was said to have been fighting off an attack.
Journalists saw two bodies near the shooting, and officials in the town morgue said three people had died of gunshot wounds. The Ukrainian police said three people had died and four were wounded. Pro-Russian militants said three of their members and two attackers had died.
Soon enough, each side interpreted the tableau of violence in its own way. The mayor of Slovyansk, Vyachislav Ponomaryov, who was appointed by the pro-Russian militants, imposed a curfew and asked President Vladimir V. Putin of Russia to send Russian peacekeepers.