SLOVYANSK, Ukraine — A military operation that the Ukrainian government said would confront pro-Russian militants in the east of the country unraveled in disarray Wednesday with the entire contingent of 21 armored vehicles that had separated into two columns surrendering or pulling back before nightfall. It was a glaring humiliation for the new government in Kiev.
Though gunshots were fired throughout the day, and continued sporadically through the evening in this town that is occupied by pro-Russian militants, it was unclear whether anybody had been wounded.
One of the armored columns stopped when a crowd of men drinking beer and women yelling taunts and insults gathered on the road before them, and later in the day its commander agreed to hand over the soldiers’ assault rifles to the very separatists they were sent to fight.
Another column from the same ostensibly elite unit, the 25th Dnipropetrovsk paratrooper brigade, surrendered not only its weapons but also the tracked and armored vehicles it had arrived in, letting militants park them as trophies, under a Russian flag, in a central square here.
A pro-Russian militant then climbed into the driver’s seat of one and spun the vehicle around on its tracks, screeching and roaring, to please the watching crowd.
The events of the day underscored the weakness of the new government in Kiev entering critical talks with the United States and Russia in Geneva on Thursday over Ukraine’s future. Unable to exercise authority over their own military, officials increasingly seem powerless to contain a growing rebellion by pro-Russian militants that has spread to at least nine cities in eastern Ukraine.
In a tactical error, the Ukrainian soldiers on Wednesday had no accompanying force to control the crowds that formed around their advancing units. Their task, to confront armed militants intermingled with civilians, would be extremely difficult for any conventional army, but for this group, which apparently lacked the tools and the heart to carry it out, it proved to be impossible.
Just placing the conventional army forces near this darker, more insidious mix of unconventional tactics risked such a setback. “You are fulfilling criminal orders!” one resident yelled at a Ukrainian soldier sitting on an armored vehicle.
The soldier said he was not, and showed that he had removed the magazine from his assault rifle. “You are saying, ‘Come over to the side of the people,’” he said. “I am a soldier. I protect the people. I won’t shoot you.”
Ukrainian military helicopters buzzed over the scene but were of no help to the soldiers’ quandary below.
They faced not only the civilians, but behind them a force of well-armed men in unmarked green uniforms, who Western governments have said are either Russian soldiers or Russian-equipped militants. These soldiers were well-armed. They carried radios and ammunition pouches. Some had rocket-propelled grenade launchers slung over their shoulders.
The Ukrainian contingent that surrendered handed over their vehicles to men in unmarked green uniforms, who made their presence more public Wednesday than it had been earlier. They drove them to the central plaza of Slovyansk, a town about 120 miles from the Russian border, and parked them there for all to see, the flags of Russia and the newly declared and wholly unrecognized People’s Republic of Donetsk flapping above them in the breeze.
In Brussels, the head of NATO said that the alliance would strengthen its military presence in Eastern Europe. Anders Fogh Rasmussen, the alliance’s secretary general, said that NATO would immediately send forces to the region as a deterrent. He did not specify how many troops or aircraft would be involved or what kind of assets would be deployed.