AT THE KHERSON FRONT, Ukraine — The commander banged on the door furiously.
“I need help!” he shouted.
When Tetiana Kozyr opened up, the commander rushed in, carrying a young soldier on his shoulders. She said the young man was sunburned, thin and gravely wounded.
The Ukrainians were trying to recapture her village, the smallest dot on the most detailed military maps. Russian forces had just blown up three Ukrainian tanks. Flames leaped off the roofs of neighboring houses.
The commander laid the young man gently down on Ms. Kozyr’s kitchen floor and then ripped open a bandage pack and thrust it against his chest and neck, which were badly bleeding. Ms. Kozyr hovered over them, feeling helpless and terrified in her own kitchen, watching the commander try to save the young man’s life.
“He looked so scared,” said Ms. Kozyr, who lived on a small farm and recounted this scene, which was corroborated by others from her village. “I had to turn away.”
Outside her house, several other Ukrainian soldiers lay face down in the grass.
Ukraine’s southern offensive was the most highly anticipated military action of the summer. Forecast by Ukrainian officials for weeks, its goal was to push the Russians back from a strategic region along the coast, bolster the confidence of a battered citizenry and prove to allies that Ukraine could make good use of Western-supplied weapons.
That push forward has continued, even as Ukraine has made a more dramatic surge this month in the northeast, routing Russian forces. Ukraine is regaining territory in the south, though slowly, and President Vladimir V. Putin of Russia is concerned enough about suffering an embarrassing setback that he has refused to let his commanders retreat from the city of Kherson, according to American officials.
But overall, the south remains a different story from the northeast. Interviews with dozens of commanders, ordinary soldiers, medics, village leaders and civilians who recently escaped the conflict zone portray a more difficult and costly campaign: The fighting is grinding, grueling and steep in casualties, perhaps the most heartbreaking battle in Ukraine right now.
Russian forces are deeply dug in here, and this weekend, the Kremlin is trying to cement its gains by holding highly contentious referendums in occupied areas to annex them. Ukrainian officials say they have little choice but to attack.
They are racing to recapture territory before the October rains turn the roads here into impassable sludge. And they need to keep showing to the world, especially before a nasty winter sets in and tests their allies’ resolve, that they can push the Russians out.
The Ukrainian government does not usually disclose casualty figures, but the soldiers and commanders interviewed in the past week portrayed the battlefield losses as “high” and “massive.” They described large offensives in which columns of Ukrainian tanks and armored vehicles tried to cross open fields only to be pounded mercilessly by Russian artillery and blown up by Russian mines.
One Ukrainian soldier, speaking anonymously because he was not authorized to publicly discuss casualties, said that during a recent assault, “we lost 50 guys in two hours.” In another place, said the soldier, who works closely with different frontline units, “hundreds” of Ukrainian troops were killed or wounded while trying to take a single village, which is still in Russian hands.
Across the occupied south — a wide crescent of fields, villages and cities along the Dnipro River and the Black Sea — the Russians have built formidable defenses: trenches zigzagging along irrigation canals; fortified bunkers; pillboxes; foxholes; even tank trenches carved out of the earth by bulldozers and covered with concrete slabs that enable the Russians to blast shells from positions that are very difficult for the Ukrainians to hit.
The Russians are determined to keep this chunk of Ukraine because it guards the Crimean Peninsula that Russia annexed in 2014. It also serves as a nexus of vital waterways and energy facilities, like the Zaporizhzhia nuclear power plant, Europe’s biggest.
Despite the high stakes, there is little face-to-face combat between the two sides, like there was in the early days of the war in the suburbs of Kyiv, the Ukrainian capital. Each Ukrainian soldier along the southern front carries an assault rifle, but few have fired their weapon.
In the south, death comes at long range. It is indiscriminate and total. When the artillery shells hit, young men press themselves to the earth, hands cupped over their ears, mouths open to let the blast wave ripple through their bodies.
“This is a different kind of war,” said Iryna Vereshchagina, a volunteer doctor working near the front lines. “We’re attacking the Russians but there’s a big payment for this.”
She said that of the hundreds of battlefield casualties she has treated, she has not seen a single gunshot wound.
“So many people are getting blown up,” she said.
She looked down at her boots.
“Sometimes,” she said, “there are just pieces of people left.”
Part of the reason Ukraine is facing stiff resistance in the south is because of its highly effective information campaign about the counteroffensive. The signals it sent were so convincing that the Russians hastily redeployed tanks, artillery and thousands of troops, including some of their better trained units, from the northeast to the south.
That left the Kharkiv region wide open for the taking, which is what happened two and a half weeks ago. But it also left the south defended by tens of thousands of well-equipped Russian soldiers. And going on the attack is always more perilous than defending an entrenched position, especially when the enemy knows the other side is coming.
All of this has unsettled some Ukrainian soldiers fighting along the front line.
“The problem is that we are advancing with no artillery preparation, without suppressing their firing positions,” said Ihor Kozub, the commander of a volunteer military unit near the southern city of Mykolaiv.
He said the Ukrainian army was suffering “great losses” because “we don’t have ammunition,” and he begged for the United States to send more.
“All these heroic attacks are made with so much blood,” he said. “It’s terrible.”
A military spokeswoman defended the Ukrainian strategy.
“The enemy’s superiority in artillery does not decide the outcome,” said Nataliia Humeniuk, the head of the communications division for Ukraine’s southern command. “History knows cases of unique battles where the quality of combat was decisive. Not the number of weapons.”
She did not provide information about the number of casualties, but Ukraine’s president, Volodymyr Zelensky, recently said that Ukraine was losing 50 soldiers a day.
The battle for the south is a lot different from Ukraine’s lightning offensive in the northeast, where the Russians troops were clearly not prepared. The Ukrainians have recaptured only a few hundred square miles in the south, less than 10 times what they recaptured in the northeast in a few days.
But Ukrainian commanders in the south always knew it was going to be a grinding battle. The strategy has been to pinch off Russian supply lines by cutting roads and destroying bridges, slowly strangling the Russians’ ability to bring in food, fuel and ammunition.
One American soldier serving with a Ukrainian unit in Mykolaiv said it was no small feat to take villages from the Russians when the Russians knew they were coming for months.
“It might look like a slog,” he said, insisting on anonymity for security reasons. “But for us, it’s progress.”
Weeks before the counteroffensive began, Ukrainian troops, including a sniper known as Pirate, started eyeing targets.
Pirate is his code name — he did not want to divulge his real name. He is 29 years old with shining blue eyes, meaty shoulders and a skull-and-crossbones patch stuck on his chest plate. For three days, he said, he lay on his stomach squinting through a scope at a squad of Russian soldiers. They were digging fortifications in a village near Kherson. Pirate and another sniper hid in a tree line almost a mile away.
At last, Pirate said, they identified the officer in charge, who was wearing a white T-shirt. Pirate and his partner calibrated their sights, gauged the wind — a soft, side wind — and counted: one, two, three. Then they squeezed their triggers.
Their two bullets flew across the open fields, outracing the speed of sound. Before he even heard the crack of the rifles, the Russian officer crumpled to the ground.
“I try not to think about who he was,” Pirate said.
He spoke from a demolished building near the front lines that has been turned into a base. This is the picture of many southern towns. They have been utterly destroyed: the schools, the homes with blown-out roofs, the power poles lying in the muddy roads, the pine trees split apart, their branches hanging down like broken arms.
Even the earth itself has been gouged by missiles and rockets, leaving moonlike craters everywhere, some with steel fins still sticking out. The smell of dried sunflowers lingers in the air. So many sunflower farms, a major industry, lie burned and deserted.
Ms. Kozyr, who had watched the wounded soldier lying on her kitchen floor, said her village had been destroyed, too. It used to be a hamlet of a few hundred people who tended small farms and raised livestock. Now no one is left. The Russians captured it in March and the Ukrainians fought hard to liberate it at the end of August, when they officially announced the beginning of the offensive. She fled a few days later and now lives in a displaced persons shelter in the city of Zaporizhzhia.
She said that when the commander first arrived with the wounded soldier, she panicked.
“I was yelling at him: ‘Why did you bring him here? The Russians will kill us all!’” she said.
But the commander just stepped through the doorway, desperate to find shelter. The village was on fire, in the middle of two armies blasting each other.
She shrunk back as her husband and the commander pressed bandages to the young man’s wounds. Shrapnel had sliced through his back and lungs. Her kitchen floor was soon covered in blood.
That night, she and her husband slept in their cellar. The commander curled up next to the wounded soldier on the kitchen floor.
When Ms. Kozyr stepped outside the next morning, to check on her calf and pigs, she passed by the kitchen and peered through the window.
The soldier’s hands were curled, his body stiff. He was dead.
She started crying at the memory of it, pulling a small rag out of her pocket and wiping her eyes. But she did not question the counteroffensive.
“It needed to be done,” she said. And then she repeated herself, a little more softly. “It needed to be done.”
Oleksandra Mykolyshyn and Oleksandr Chubko contributed reporting from Mykolaiv, Ukraine, and Thomas Gibbons-Neff from Pokrovsk, Ukraine.