AVDIYIVKA, Ukraine -- "Attack. Counterattack. Attack. Counterattack."
That's how Kyiv regiment commander Yevhen Deydey described the battlefield maneuvering taking place on February 2, as Russia-backed separatists stepped up attacks against Ukrainian government forces in this embattled eastern Ukrainian city for a fifth straight day.
Ukraine bolstered its defenses with scores more troops and large-caliber artillery, including main battle tanks, which were seen by RFE/RL trundling toward the front line and positioned in the courtyard of a nine-story apartment building pocked with massive holes from direct artillery strikes.
Our tanks are preparing for battle. This is a real escalation."-- Commander Yevhen Deydey
These sorts of heavy weaponry are supposed to remain well back from here, under a 2-year-old cease-fire deal that international monitors say has been routinely violated by Ukrainian forces and the Russia-backed separatists they are fighting.
"Our tanks are preparing for battle," Deydey said inside the Ukrainian Army's forward-most command center, peering out a shattered window at his arsenal standing by in the courtyard. "This is a real escalation."
The outburst of violence since January 29 has shattered a monthslong relative lull in fighting, pushed the city of Avdiyivka to the brink of a humanitarian catastrophe, and heightened fears that full-scale warfare could reignite at any moment.
The racket of small arms, mortars, howitzers, and even tank fire -- collectively referred to by soldiers as "the disco" -- never let up here on February 2, and, in fact, grew in intensity throughout the day. The rumbling of Grad rockets pierced the winter chill as they came crashing down on military positions and civilian homes, not in ones and twos but by the truckload. Each multiple-launch rocket system carries up to 40 of them.
Ukraine's military said fighting had pushed the death toll to at least 23 people, including civilians, since January 29 and closer to a total of 10,000 since the war erupted in April 2014.
Yulia Paevska, a volunteer medic who goes by the nickname "Tyra" after the U.S. supermodel-turned-TV-personality Tyra Banks and calls her colleagues her "angels," told RFE/RL she had not seen fighting on this scale in Avdiyivka for two years.
"There is so much Grad. And it's so expensive. I have no idea who pays for it," she said in a nod to Russia's putative -- but stridently denied -- support for the separatists.
Paevska said her team treated five wounded soldiers on February 2, including one with a serious shrapnel wound to his leg. She had been awakened four times overnight by incoming shelling.
Deydey saw a Russian hand in the tactics employed by fighters on the other side, who he said made several attempts to outflank his soldiers but were repelled by the Ukrainians.
"When the artillery strikes are especially accurate, and repeatedly, we know it's professional [Russian] army guys," he said.
Deydey displayed evidence of what he said was Russian psychological warfare targeting Ukrainian defense forces: text messages sent from mysterious numbers addressed to Ukrainian soldiers that read, "You are just meat to your commanders," "Your body will be found when the snow melts," and, "You're like the Germans in Stalingrad."
He shrugged off the messages and said he did not want to have to fight and would prefer peace.
"We have tried for a cease-fire," he said, "but each time it is broken in minutes."
Russia has denied direct involvement in the fighting, and President Vladimir Putin at a news conference in Budapest on February 2 accused Kyiv of provoking the latest lethal bout and using it as a ploy to win support from new U.S. President Donald Trump.
Trump's flattery of Putin has prompted considerable anxiety in Kyiv, which fears the new U.S. administration may lift sanctions imposed against Russia after its seizure of Crimea from Ukraine in 2014.
WATCH: Intense Fighting Prompts Evacuations In Eastern Ukraine
The new U.S. ambassador to the United Nations, Nikki Haley, sought to assure Kyiv and others of Washington's commitment to Ukrainian territorial integrity on February 2. In her first public statement from the UN Security Council, Haley called Crimea "a part of Ukraine" and vowed, "Our Crimea-related sanctions will remain in place until Russia returns control of the peninsula to Ukraine."
She said the "dire situation" in Ukraine as fighting surges "demands clear and strong condemnation of Russian actions."
Residents of Avdiyivka who have been without electricity, water supplies, and heating in temperatures well below freezing since January 29, when shelling knocked out power to this city of around 22,000 people, would love nothing more than a respite from the violence.
But within hours of Haley's remarks in New York, Avdiyivka residents Tamara and Olena told RFE/RL early on February 3 that they had spent the night in a cellar.
"The artillery was nonstop," Tamara said, the worst since January 29.
Another local, Serhiy Kovalenko, thrust a gloved hand out to show two pieces of shrapnel that he said came from a blast overnight in the courtyard of his mother's apartment.
"Return this to Putin and tell him the sad people of Avdiyivka say thank you," he added.
Oleksandr, a pensioner who lives in the old town that butts up against the front line, said on February 2 that the level of fighting was "probably worse" than it was in 2014. He did not provide his last name out of fear of being seen as critical of Ukraine's government.
"Unfortunately, [this violence] is nothing new," Oleksandr said, gesturing to the summer kitchen in his yard that was obliterated by a shell late on February 1. "We have been living this nightmare for two years."
And yet, like most people here, he won't leave.
"I was born here and I will die here," he said. "If it's [by a shell], so be it.
"We all end up in the ground somehow."
