Dozens of Ukrainian emergency workers laboured Sunday to pull people out of the rubble after a Russian rocket attack smashed into apartment buildings in eastern Ukraine, killing at least 15 people. More than 20 people were believed still trapped.

The strike late Saturday destroyed three buildings in a residential quarter of the town of Chasiv Yar, inhabited mostly by people who work in nearby factories.?

On Sunday evening, rescuers were able to remove enough of the bricks and concrete to retrieve a man who had been trapped for almost 24 hours. Rescuers laid him on a stretcher and he was quickly taken to hospital.

Ukraine's Emergency Services said the latest rescue brought to six the number of people dug out of the rubble. Earlier in the day, they made contact with three others still trapped alive beneath the ruins.

Pavlo Kyrylenko, governor of the Donetsk region that includes Chasiv Yar, said an estimated 24 people were believed still trapped, including a 9-year-old child.?

Cranes and excavators worked alongside rescue teams to clear away the ruins of one building, its walls completely shorn off by the impact of the strike. The rescuers kept working in the rain despite the dangerous conditions. The thud of artillery on the nearby front line resonated just a few miles away, making some workers flinch and others run for cover.

Kyrylenko said the town of about 12,000 was hit by Uragan rockets that are fired from truck-borne systems. Chasiv Yar is 20 kilometers (12 miles) southeast of Kramatorsk, a city that is a major target of Russian forces as they grind westward.

However, later Sunday, Viacheslav Boitsov, deputy chief of emergency service in the Donetsk Region, told the Associated Press that four shells hit the neighborhood and they were likely Iskander missiles.

Residents said they heard at least three explosions in the attack and that many people were badly wounded in the blasts. A group of neighbors sat Sunday in a courtyard quietly discussing who was wounded and who was still missing.

“There was an explosion, all the windows blew out and I was thrown to the ground, said 45-year-old Oksana, who gave only her first name. She was in her third-floor apartment when the missiles struck.

“My kitchen walls and balcony have completely vanished,” she added, struggling to hold back tears. ”I called my children to tell them I was alive."?

Irina Shulimova, a 59-year-old retiree, recalled the terror. “We didn't hear any incoming sound, we just felt the impact. I ran to hide in the corridor with my dogs. Everyone I knew started calling me to find out what had happened. I was shaking like a leaf,” she said.

Front doors and balconies were torn apart in the blast, and heaps of twisted metal and bricks lay on the ground. Crushed summer cherries lay among shattered window panes.

A 30-year-old technology worker named Oleksandr said his mother was among those injured in the explosion.

“Thank God I wasn't injured, it was a miracle,” he said, touching the crucifix around his neck.

Although the home he shares with his mother is now shattered, he said he doesn't plan to leave the neighborhood.?

“I only have enough money to support myself for another month. Lots of people are fed up already of refugees coming from the east — no one will feed or support us there. It's better to stay,” said Oleksandr, who declined to give his surname.

Another resident who gave only his first name, Dima, had lived for more than 20 years on the ground floor of one of the buildings that was hollowed out in the attack. He walked back and forth across the rubble.

“As you can see, my home is lost,” he said.

Saturday's attack was the latest in a series of strikes against civilian areas in the east, even as Russia repeatedly claims it is only hitting targets of military value in the war.

Twenty-one people were killed earlier this month when an apartment building and recreation area came under rocket fire in the southern Odesa region. Another at least 19 people died when a Russian missile hit a shopping mall in the city of Kremenchuk in late June.

There was no comment about the Chasiv Yar attack at a Russian Defense Ministry briefing on Sunday.

The Donetsk region is one of two provinces along with Luhansk that make up the Donbas region, where separatist rebels have fought Ukrainian forces since 2014. Last week, Russia captured the city of Lysychansk, the last major stronghold of Ukrainian resistance in Luhansk.

Russian forces are raising “true hell” in the Donbas, despite assessments they were taking an operational pause, Luhansk governor Serhiy Haidai said Saturday.

After the seizure of Lysychansk, some analysts predicted that Moscow's troops likely would take some time to rearm and regroup.?

But “so far there has been no operational pause announced by the enemy. He is still attacking and shelling our lands with the same intensity as before,” Haidai said.?

He later said Ukrainian forces had destroyed some ammunition depots and barracks used by the Russians.