KYIV, Ukraine -- Russia and Ukraine accused each other Friday of shelling a prison in a separatist region of eastern Ukraine, an attack that reportedly killed dozens of Ukrainian prisoners of war captured after the fall of Mariupol, the city where troops famously held out against a months-long Russian siege.
Both sides said the assault was premeditated with the aim of covering up atrocities.
Russia claimed that Ukraine's military used U.S.-supplied rocket launchers to strike the prison in Olenivka, a settlement controlled by the Moscow-backed Donetsk People's Republic. Separatist authorities and Russian officials said the attack killed 53 Ukrainian POWs and wounded another 75.
Moscow opened a probe into the attack, sending a team to the site from Russia's Investigative Committee, the country's main criminal investigation agency. The state RIA Novosti agency reported that fragments of U.S.-supplied precision High Mobility Artillery Rocket System rockets were found at the site.
The Ukrainian military denied making any rocket or artillery strikes in Olenivka, and it accused the Russians of shelling the prison to cover up the alleged torture and execution of Ukrainians there. An adviser to Ukrainian President Volodymyr Zelenskyy described the shelling as "a deliberate, cynical, calculated mass murder of Ukrainian prisoners."
Neither claim could be independently verified.
Denis Pushilin, the leader of the internationally unrecognized Donetsk republic, said the prison held 193 inmates. He did not specify how many were Ukrainian prisoners of war.
The deputy commander of the Donetsk separatist forces, Eduard Basurin, suggested that Ukraine decided to strike the prison to prevent captives from revealing key military information.
Ukraine "knew exactly where they were being held and in what place," he said. "After the Ukrainian prisoners of war began to talk about the crimes they committed, and orders they received from Kyiv, a decision was made by the political leadership of Ukraine: carry out a strike here."
Ukrainian presidential adviser Mykhailo Podolyak called for a "strict investigation" into the attack and urged the United Nations and other international organizations to condemn it. He said the Russians had transferred some Ukrainian prisoners to the barracks just a few days before the strike, suggesting that it was planned.
"The purpose -- to discredit Ukraine in front of our partners and disrupt weapons supply," he tweeted.
Ukrainian officials alleged that Russia's Wagner Group, mercenaries Russia has used in other armed conflicts and reportedly elsewhere in Ukraine, carried out the assault.
Ukraine's security agencies issued a statement citing evidence that Russia was responsible, including the transfer of prisoners, analysis of injuries and the blast wave, intercepted phone conversations and the absence of shelling at the site.
"All this leaves no doubt: The explosion in Olenivka was a Russian terrorist act and a gross violation of international agreements," the statement said.
A Russian Defense Ministry spokesperson, Lt. Gen. Igor Konashenkov, described the strike as a "bloody provocation" aimed at discouraging Ukrainian soldiers from surrendering. He too claimed that U.S.-supplied High Mobility Artillery Rocket Systems were used and said eight guards were among the wounded.
Ukrainian forces are fighting to hold on to the remaining territory under their control in Donetsk. Together with the neighboring Luhansk province, they make up Ukraine's mostly Russian-speaking industrial Donbas region.
For several months, Moscow has focused on trying to seize parts of the Donbas not already held by the separatists.
Holding POWs in an area with active fighting appeared to defy the Geneva Convention, which requires that prisoners be evacuated as soon as possible after capture to camps away from combat zones.
The Ukrainian POWs at the Donetsk prison included troops captured during the fall of Mariupol. They spent months holed up with civilians at a giant steel mill in the southern port city. Their resistance during a relentless Russian bombardment became a symbol of Ukrainian defiance against Russia's aggression.
More than 2,400 soldiers from the Azov Regiment of the Ukrainian national guard and other military units gave up their fight and surrendered under orders from Ukraine's military in May.
Scores of Ukrainian soldiers have been taken to prisons in Russian-controlled areas. Some have returned to Ukraine as part of prisoner exchanges with Russia, but the families of other POWs have no idea whether their loved ones are still alive, or if they will ever come home.
ZELENSKYY VISITS PORT
Zelenskyy visited a Black Sea port Friday to watch crews prepare to export grain trapped by Russia's five-month-old war, a week after a deal was struck to allow critical food supplies to flow to millions of impoverished people facing hunger worldwide.
"The first vessel, the first ship is being loaded since the beginning of the war," Zelenskyy told reporters as he stood next to a Turkish-flagged ship at the Chornomorsk port in the Odesa region.
He said the departure of wheat and other grain will begin with ships that were already loaded but could not leave Ukrainian ports after Russia invaded in late February.
Ukraine is a key global exporter of wheat, barley, corn and sunflower oil. Their loss has raised global food prices, threatened political instability and helped push more people into poverty and hunger in already vulnerable countries.
Ukraine's military is committed to the ships' safety, said Zelenskyy, adding, "It is important for us that Ukraine remains the guarantor of global food security."
His unannounced visit to the port is part of Ukraine's push to show the world that it is nearly ready to export millions of tons of grains under last week's breakthrough agreements, which were brokered by Turkey and the United Nations and signed separately by Ukraine and Russia.
The sides agreed to facilitate the shipment of wheat and other grains from three Ukrainian ports through safe corridors on the Black Sea, as well as fertilizer and food from Russia.
But a Russian missile strike on Odesa hours after signing the deal threw Moscow's commitment into question and raised concerns about the safety of shipping crews, who also have to navigate waters strewn with explosive mines.
Russia's deputy U.N. ambassador Dmitry Polyansky told the U.N. Security Council in New York on Friday that Ukraine has been deploying military goods and hardware in the port of Odesa, "and we will continue to destroy these goods and objects, as we did on July 23."
Kremlin spokesman Dmitry Peskov emphasized the "link between taking grain out of Ukrainian ports and unblocking direct or indirect restrictions on the export of our grain, fertilizers and other goods to global markets."
The security concerns and complexities of the agreements have set off a slow, cautious start. The clock is ticking -- the deal is only good for 120 days.
The goal over the next four months is to export some 20 million tons of grain from three Ukrainian sea ports blocked since the Feb. 24 invasion. That provides time for four to five large bulk carriers per day to transport grain from the ports to millions of people in Africa, the Middle East and Asia, who are already facing food shortages and, in some cases, famine.
Getting the grain out is also critical to farmers in Ukraine, who are running out of storage capacity because of a new harvest.
"We are ready," Ukraine's minister of infrastructure, Oleksandr Kubrakov, told reporters at the port of Odesa on Friday.
But he said Ukraine is waiting on the U.N. to confirm the safe corridors that ships will use. In the meantime, a ship at the port of Chornomorsk was being loaded with grain, he said.
Lloyd's List, a global shipping news publisher, noted that while U.N. officials are pushing for the initial voyage this week to show progress, uncertainty on key details will likely prevent an immediate ramping-up of shipments.
"Until those logistical issues and detailed outlines of safeguarding procedures are disseminated, charters will not be agreed and insurers will not be underwriting shipments," wrote Bridget Diakun and Richard Meade of Lloyd's List.
They note, however, that U.N. agencies, such as the World Food Program, have already arranged to charter much of the grain for urgent humanitarian needs.
Shipping companies have not rushed in because explosive mines are drifting in the waters, ship owners are assessing the risks and many question how the agreement will unfold.
The deal stipulates that Russia and Ukraine provide "maximum assurances" for ships that brave the journey to the Ukrainian ports of Odesa, Chornomorsk and Yuzhny.
Smaller Ukrainian pilot boats will guide the vessels through approved corridors. The entire operation will be overseen by a Joint Coordination Center in Istanbul staffed by officials from Ukraine, Russia, Turkey and the United Nations.
Once ships reach port, they will be loaded with grain before departing back to the Bosphorus Strait, where they will be boarded to inspect them for weapons. There will likely be inspections for ships embarking to Ukraine as well.
CIVILIANS KILLED
In other developments Friday, the Ukrainian presidential office said at least 13 civilians were killed and another 36 wounded in Russian shelling over the last 24 hours.
In the southern city of Mykolaiv, at least four people were killed and seven others wounded when Russian shelling hit a bus stop. The Russian barrage also hit a facility that distributed humanitarian aid where three people were wounded, officials said.
Ukrainian officials also said at least four civilians were killed and five hurt in the eastern town of Bakhmut in the Donetsk region.
An appeals court in Kyiv on Friday reduced to 15 years the life sentence of a Russian soldier convicted in the first war crimes trial since Russia invaded Ukraine.
Critics had said the sentencing of Vadim Shishimarin, 21, was unduly harsh given that he confessed to the crime and expressed remorse. He pleaded guilty to killing a civilian and was convicted in May.
His defense lawyer argued that Shishimarin shot a Ukrainian man on the orders of his superiors.
Information for this article was contributed by Susie Blann, Inna Varenytsia, Aya Batrawy, Suzan Fraser and Edith M. Lederer of The Associated Press.
FILE - Smoke rises from the Metallurgical Combine Azovstal in Mariupol, in territory under the government of the Donetsk People's Republic, eastern in Mariupol, Ukraine, on May 5, 2022. Russia-backed separatists in eastern Ukraine say that at least 40 Ukrainian prisoners of war captured during the fighting for Mariupol have been killed by Ukrainian shelling. (AP Photo, File)
EDS NOTE: GRAPHIC CONTENT - Investigators examine bodies of Ukrainian military prisoners at a prison in Olenivka, in an area controlled by Russian-backed separatist forces, eastern Ukraine, Friday, July 29, 2022. Russia and Ukraine accused each other Friday of shelling a prison in Olenivka, a separatist region of eastern Ukraine, an attack that reportedly killed dozens of Ukrainian prisoners of war who were captured after the fall of a southern port city of Mariupol in May. (AP Photo)
A soldier stand guard next to a wall of a prison in Olenivka, in an area controlled by Russian-backed separatist forces, eastern Ukraine, Friday, July 29, 2022. Russia and Ukraine accused each other Friday of shelling a prison in a separatist region of eastern Ukraine, an attack that reportedly killed dozens of Ukrainian military prisoners who were captured after the fall of a southern port city of Mariupol in May. (AP Photo)
FILE - Smoke rises from the Metallurgical Combine Azovstal in Mariupol during shelling, in Mariupol, in territory under the government of the Donetsk People's Republic, eastern Ukraine, Saturday, May 7, 2022. Russia-backed separatists in eastern Ukraine say that at least 40 Ukrainian prisoners of war captured during the fighting for Mariupol have been killed by Ukrainian shelling. (AP Photo/Alexei Alexandrov, File)
In this photo taken from video a view of a destroyed barrack at a prison in Olenivka, in an area controlled by Russian-backed separatist forces, eastern Ukraine, Friday, July 29, 2022. Russia and Ukraine accused each other Friday of shelling a prison in a separatist region of eastern Ukraine, an attack that reportedly killed dozens of Ukrainian military prisoners who were captured after the fall of a southern port city of Mariupol in May. (AP Photo)
EDS NOTE: GRAPHIC CONTENT - In this photo taken from video a view of destroyed barrack at a prison in Olenivka, in an area controlled by Russian-backed separatist forces, eastern Ukraine, Friday, July 29, 2022. Russia and Ukraine accused each other Friday of shelling a prison in a separatist region of eastern Ukraine, an attack that reportedly killed dozens of Ukrainian military prisoners who were captured after the fall of a southern port city of Mariupol in May. (AP Photo)
A grain terminal spout stands idle at the Odesa Sea Port, in Odesa, Ukraine, Friday, July 29, 2022. (AP Photo/David Goldman)
In this photo provided by the Ukrainian Presidential Press Office, Ukrainian President Volodymyr Zelenskyy, center, surrounded by ambassadors of different countries and UN officials, visits a port in Chornomork during loading of grain on a Turkish ship, background, close to Odesa, Ukraine, Friday, July 29, 2022. (Ukrainian Presidential Press Office via AP)
This image from video shows the destroyed barracks at a prison in Olenivka in eastern Ukraine where dozens of Ukrainian prisoners reportedly were killed. The area is controlled by Russian-backed separatist forces. (AP)Gallery: Images from Ukraine, month 6
