Pro-Russian residents are setting up barricades to keep Ukrainian troops out as Ukrainian forces launch what seems to be their first major assault against the separatists. (Associated Press)

A cigarette shook in Natalya Botte’s hand as she told the story of her “hellish” morning. Helicopters, shootings, explosions: She thought it could only happen somewhere in the Middle East, but on Friday the war came to her home town in eastern Ukraine.

“We should be evacuated, but Kiev thinks of us as terrorists,” said Botte, 26, referring to Ukraine’s capital. “They fly above our heads shooting all day, but there is an orphanage here full of kids, and we have children at home.”

Botte, who said her husband was in jail, said she had heard shooting and two loud explosions between 4 a.m. and 7 a.m., adding that she and her 2-year-old daughter had been scared and unable to sleep. They were not alone.

The men of Slovyansk and its suburbs rushed to barricade their neighborhoods Friday morning, using sandbags and logs in an attempt to prevent Ukrainian armored vehicles from driving into town.

Armed pro-Russian protestors sit on a checkpoint in Slovyansk. (Roman Pilipey/EPA)

“Where is Putin and his army?” Botte asked the pro-Russian men outside a checkpoint still controlled by separatists despite the early-morning attack by Ukrainian government forces. Nobody could tell her.

At a burning barricade manned by rebels, a masked fighter who gave his name as Thunder said he had two children and a pregnant wife at home. “I believe the Russian army will be here soon,” he said. “It is time.”

The fighter said he wished with all his heart that the Russian army would arrive to help. “Otherwise, there is nothing else for me left to do but die defending my two children with this,” he said, lifting his Kalashnikov automatic rifle.

In this image taken from Rossia 24 television channel TV, an injured Ukrainian military helicopter pilot is assisted by pro-Russian activists after he was shot down in Slovyansk. (Rossia 24 Television Channel/AP)

Ukraine’s government said it was sending in troops to protect civilians from the “terrorists” who had taken over the city, but few residents of Slovyansk saw the distinction. Many felt they had been branded terrorists themselves.

Pro-Russian rebels stand guard at a checkpoint near a Ukrainian airbase in Kramatorsk. (Marko Djurica/Reuters)

In the nearby town of Kramatorsk, militiamen blocked roads with trolley cars and buses in an attempt to prevent the army from entering, while residents of the village of Andreevskoe linked arms to form a human chain to keep troops out. Many held Russian Orthodox icons.

The streets of Slovyansk were largely deserted Friday, with armed men in a mixture of camouflage and ordinary civilian clothes manning barricades. Some wore balaclavas over their faces. Some were clearly ordinary civilians, but a few dozen “green men” looked like professional soldiers. A few of them said in interviews they were “born in the U.S.S.R.”

By noon Friday, Ukrainian troops in armored personnel carriers had surrounded the town and called on pro-Russian leaders to free hostages and give up their weapons.

The militants guarding barricades downtown looked nervous, ready to open fire at every approaching vehicle.

A block away from the central Lenin Square, five rough-looking gunmen demanded that reporters get out of their car and slowly walk toward a barricade.

“Hold your arms up!” a man holding a pistol with both hands shouted as the journalists walked closer to present him with their credentials. At least 10 other journalists were briefly detained in the neighboring town of Kramatorsk.

Many residents moved their families from Slovyansk and Kramatorsk this month. Those who stayed were either determined to help the rebels defend their town or simply had no resources for travel.

Unmarked soldiers wait on the road to Kramatorsk. (Igor Kovalenko/EPA)

A coffee shop owner who gave his name only as Alexander was sleeping on a small couch in his cafe when the Ukrainian military stormed the rebels’ checkpoint on the road from Slovyansk to Izyum, 20 miles to the north, at 5 a.m. He got up to see pro-Russian militants carrying their wounded away from the front line into the woods.

Alexander was wounded, but would not explain how. His left hand was bleeding through a bandage, but he continued to make coffee for his clients. “I hate Kiev for ordering an attack on us peaceful people, but I would make coffee for Ukrainian military too, as long as they pay me money,” Alexander said.

Ukraine’s men in masks

Reuters photographer Marko Djurica asked a group of pro-Russian separatists in Donetsk, where they have occupied several government buildings, to pose for portraits inside a building they now control.