The ambush was the deadliest of surprises:
As far as the battered and encircled Ukrainian troops understood, they were to be granted safe passage by the Russians — a so-called "green corridor" — back to friendly territory after days of fierce fighting.
But it didn't turn out that way.
Instead, tanks, artillery, and machine gun fire blew apart their convoy as it sped away in panic, leaving bodies scattered and machinery burning across desolate fields and dirt roads.
"It ended up as a corridor of death," Yatsyk says.
He was one of about 1,200 Ukrainian volunteer and professional troops who fought in the Battle of Ilovaisk, which ended on Aug. 29, 2014 in a disastrous Ukrainian defeat that forced Kiev to the negotiating table in Minsk.
It's still the bloodiest battle of the year-long war, which continues to grip Ukraine despite two ceasefires and other diplomatic efforts to end the violence that's killed nearly 7,000 people.
First, there was the ill-prepared assault on the strategic city.
Then came the resulting encirclement by Russian and separatist forces.
Finally, the most tragic episode: several hundred Ukrainian troops were massacred as they tried to leave.
The battle marked what Ukrainian officials claim was Russia's open invasion of eastern Ukraine.
But it also sparked widespread public anger and raised questions over the military chiefs' mismanagement — and, possibly, their outright betrayal.
Now, on the first anniversary of the Battle of Ilovaisk, critics are decrying the slow pace of an official investigation into the affair.
They say those responsible for giving bad orders, or none at all, remain untouched.
"In principle, conclusions were drawn and lessons learned on many issues," said Mykola Sungurovsky, a military analyst in Kiev.
"Unfortunately, those conclusions didn't involve personnel, those who managed the entire thing."
Meanwhile, Ukraine's military continues to grapple with some of the very dilemmas — like a lack of resources and poor leadership — that first came to the fore a year ago.
And there is no end in sight to the pro-Russian rebellion that continues to smolder in eastern Ukraine, stoking the most serious tensions between Russia and the West since the Cold War.
Doomed from the start?
By the time Ukrainian forces attempted their first assault on Ilovaisk early last August, the military had regained considerable territory from Russian-backed separatists, and it seemed like they might actually beat the rebels soon.
Taking Ilovaisk meant cutting crucial supply lines between the rebel capital of Donetsk and Russia, which steadily provided mercenaries and battle gear.
Yatsyk's unit, part of the volunteer Donbass Battalion, the largest militia force in the operation, entered the city on Aug. 18.
It was the third and final assault, meant to drive out the separatists and secure the city once and for all.
Previous attempts by other units had been unsuccessful.
Ukrainian volunteer forces, equipped with little more than Kalashnikov rifles and rocket-propelled grenades, were quickly able to take half of Ilovaisk.
But by the second day, Yatsyk says, it was clear something wasn't right.
There were far more rebel troops hunkered down in the city than first expected.
The Ukrainians were soon halted by stiff resistance as well as a lack of armor and support from the flanks, where other units weren't able to break through.
Still, they fought on for days, facing multiple daily attacks with Grad rockets and other heavy artillery.
Reinforcements never came.
"They [military leadership] kept feeding us promises like, ‘Tomorrow you'll receive lots of reinforcements, we'll storm both sides of the city and Ilovaisk will be ours,'" Yatsyk recalls in an interview with GlobalPost.
"But all that remained on the level of words."
While waiting for help, he added, around a dozen men in the Donbass Battalion alone were killed.
That's in addition to losses sustained by other volunteer units, whose original purpose was to sweep cities after infantry assaults — not to lead them.
The Russians are coming
Several days into the assault, Kiev's intelligence reports found that a Russian invasion force of nearly 4,000 troops had broken through the border, around half of which were headed toward Ilovaisk.
Yuri Butusov, an influential journalist and top military expert, says several agencies — including the state border guards — reported the incursion to Ukraine's military leadership as early as Aug. 23, 2014.
That's in line with a parliamentary investigation into the battle.
But this month, the Defense Ministry said it was able to confirm the Russian invasion only on Aug. 26 of last year, citing potential disinformation.
Many critics dismiss that claim.
"There was not the slightest reason to doubt the veracity of this information," Butusov wrote in a report earlier this month, blaming the chief of the general staff, Viktor Muzhenko, for failing to respond in time.
For Yatsyk and others on the ground in Ilovaisk, the Russian invasion wasn't exactly a secret.
Over the course of the battle, Ukrainian forces had captured 10 Russian paratroopers and a Russian tank.
By Aug. 25 of last year, Yatsyk says word of the Russians' presence had reached him and his men.
But it finally sank in after he was shown the captured tank three days later.
"That's when I understood [we were fighting Russians]," he says.
"But in terms of their numbers, that information wasn't available to us."
Russian forces and separatist rebels gradually surrounded the outgunned and outnumbered Ukrainians, tightening the "cauldron," a Soviet-era military term describing a complete encirclement.
There were apparently few reserves available to reinforce the Ukrainian positions, the most crucial of whom — on the Ukrainian-Russian border — had been reportedly abandoned under heavy fire.
What's worse, critics say, there were no orders from Kiev to retreat.
Meanwhile, back in Kiev, on Aug. 28, the chief military spokesman told reporters the situation in Ilovaisk was "under control."
That's despite pleas on Facebook from injured Donbass Battalion chief Semen Semenchenko begging for generals to relieve the besieged troops.
A deadly scramble
With few other options, the Ukrainians were eventually forced to negotiate on Aug. 28, 2014 for safe passage back to Ukraine-controlled territory.
Muzhenko, the general staff chief, says he held talks with his counterpart in the Russian high command to discuss the plan — a claim others dispute.
But talks between lower-ranking commanders on both sides did take place that day, continuing into the morning of Aug. 29.
The Russians reportedly delayed several hours, changing the conditions for the exit.
Hearing of the negotiations, the Ukrainian troops expected orders for a swift and orderly withdrawal after days of encirclement.
But as his column of around 400 Ukrainians waited to leave through the corridor from a suburb just south of Ilovaisk, Yatsyk claims an infamous rebel commander, nicknamed "Motorola," broke through their communication lines.
The rebel commander trolled Yatsyk and his men over the radio, warning of their imminent demise.
"But through profanity," Yatsyk adds.
Shortly after, he says, the mortar fire began.
To escape, Yatsyk's convoy of armored vehicles and buses hightailed it a couple of miles farther south through open fields.
There, Russian tanks and artillery were dug into prime positions — thanks to the delays in negotiations, officials say — and the turkey shoot began.
The Russians fired at will on the Ukrainians from both sides, decimating the convoy.
"The first vehicles to burst into flames were ones with the wounded inside, with red crosses painted on them, flying white flags," Yatsyk said.
Parts of the battered convoy stopped in the next village, where regular Russian forces were concentrated.
Incredibly, the Ukrainians fought back, destroying two Russian tanks and taking around seven prisoners.
But when Yatsyk and others attempted to trade the prisoners in exchange for a safe exit from the Russians, talks broke down.
"We told them we have their prisoners," the Ukrainian ex-platoon commander says, "and they said it didn't matter."
Then the Russians fired some more, Yatsyk claims, killing several more Ukrainian troops.
Burdened by their own wounded, the Ukrainians wound up in Russian custody and passed over to the rebels two days later, despite promises to the contrary.
Yatsyk was released in late December, four months later.
Lying Russia still denies any direct involvement in the conflict.
As for the captured paratroopers, Russian officials claimed they had crossed the border by accident.
In terms of losses in the so-called green corridor, Yatsyk estimates around 100 men in his column alone were killed that day.
According to figures released this month by Ukraine's military prosecutor, 366 troops were killed in the Battle of Ilovaisk, and nearly 450 wounded.
More than 150 of the dead remain unidentified.
Those are conservative figures, some believe:
On Wednesday, the head of the parliamentary investigation into the affair claimed the total number of Ukrainian casualties for the entire operation may actually reach 1,000.
Many of the volunteer fighters were ordinary men from a broad range of backgrounds and professions, from IT workers to street activists who participated in Kiev's street revolution.
Though Yatsyk, an avid poker enthusiast, served a stint in the armed forces years ago, many of his comrades-in-arms had little training and received meager monthly salaries of a couple hundred dollars.
The massacre outraged the public.
It exposed nearly every Ukrainian military weakness at the time: a lack of resources, poor coordination, and the apparent inaction of top brass.
To this day, a high-profile blame game continues to muddy the picture of events.
Volunteer fighters blame the military leadership for sending their poorly armed militias — created to fulfill what were essentially police functions — to lead a frontal assault on Ilovaisk, and then leaving them in the lurch.
From his view on the ground, Yatsyk says top commanders should've acted more quickly after troops realized there were far more than 100 separatists in the city.
"At that point, it was necessary to make decisions and adjustments based on that [new] information," he says.
In turn, Muzhenko, the head of the general staff, recently claimed it was the Interior Ministry and its volunteer battalions' own idea to storm Ilovaisk in the first place.
He also blamed some of them for not showing up for the initial assault.
Many others accuse Muzhenko and his cohort of failing to act swiftly on intelligence that clearly reported Russia's invasion.
They say the failure to quickly order a withdrawal directly led to the massacre.
Meanwhile, the military prosecutor's office has asked for several more months to conclude its own investigation, dimming prospects for a speedy result.
Yet after a year of war, some lessons have been learned, according to military expert Sungurovsky, head of defense research at the Razumkov Center think tank.
Practically all volunteer battalions have since been subordinated either to the Interior or Defense Ministries, for example, and coordination among them and the regular army has improved, he says.
The military is in the process of reforming itself, though not without serious difficulties, such as bureaucracy and corruption.
Leonid Polyakov, a former deputy defense minister, agrees.
He says the defeat at Ilovaisk forced Ukraine into self-reflection about military logistics, political leadership, and waging war against a well-trained army.
"We introduced these lessons, and will continue to introduce them, into our life through legislation, regulations, organizational changes, and other developments," he said.
But discontent with the war effort has never quite abated.
The Ilovaisk tragedy resulted in the first serious loss of faith in the military leadership by citizens and soldiers alike.
It also continues to cause an uneasy relationship between the official political-military establishment and volunteer battalions, who went on to play key roles in nearly every major battle since then.
Sergei Korotkikh, reconnaissance commander for the volunteer Azov Battalion, which also fought at Ilovaisk, believes the regular army is still riddled with incompetence.
He praises the troops for their bravery and resilience, but accuses their leadership of negligence.
"We have a headquarters, we have a command center, we have some sort of combat planning, a layout of tasks, and all the rest," he told GlobalPost in an interview earlier this month, speaking about Azov's resources.
"In the year I've spent on the front, the best-case scenario [for the regular army] I've seen has been a map unfurled over the trunk of a car."
That corresponds to other reports from the front, where troops still complain of being under-equipped and neglected, and they blame political and military leaders.
A year of war has also eroded some Ukrainians' desire to join the fight:
During the latest wave of mobilization, the Defense Ministry said it pulled in only around half its target of 25,000 men.
Even after they return home, both volunteer fighters and regular soldiers still sometimes struggle to receive veterans' benefits, critics say.
Yatsyk, who is now a member of a veterans' association for volunteer fighters, says one of his comrades-in-arms is still trying to prove he fought on the front, despite being taken prisoner for some 120 days.
"I want to believe that the higher leadership knows what it's doing, where it's taking the country, that there is some strategy and steps it's following consistently," he said.
"But what's actually happening is unclear."