Updated

Captured Ukrainian soldiers were paraded through the streets of the rebel stronghold of Donetsk on Sunday as bystanders pelted them with eggs, water bottles and tomatoes, hours after Ukraine marked the 23rd anniversary of its independence from the former Soviet Union with a military parade through the capital, Kiev.

In Donetsk, thousands gathered in the main square as the insurgents staged their own spectacle mocking the national army. To jeers and catcalls, dozens of captive soldiers, some wearing tattered Ukrainian military uniforms and some in torn and dirty civilian clothing, were forced to march past as nationalistic Russian songs blared from loudspeakers. They were flanked by rebels pointing bayoneted rifles.

One visibly agitated man yelled slurs as he held an infant in one arm. "Hang the fascists from a tree!" one woman shouted as other women rushed at the prisoners, trying to kick and slap them.

Two water trucks followed the captives, hosing down the road in a move apparently meant to cleanse the pavement where the Ukrainian soldiers had passed. The image had historical parallels as well: In 1944, Red Army soldiers paraded tens of thousands of German prisoners of war through the streets of Moscow.

The top rebel commander sent a mocking message to the Ukrainian government.

"Kiev said that on the 24th, on the Independence Day of Ukraine, they would have a parade. Indeed, they did march in Donetsk, although it wasn't a parade," Alexander Zakharchenko said. "Soldiers of the armed forces of Kiev walked along the main streets of Donetsk. What [President] Poroshenko planned has taken place."

Several fire-blackened, shrapnel-shredded Ukrainian military vehicles were put on display in Donetsk's main square, where supporters posed for photos in front of one of the destroyed tanks. One onlooker grabbed a Ukrainian flag from the wreckage of one tank and threw it to the ground. Several others trampled on it, wiping their feet and spitting.

"Today is the so-called independence day of what was Ukraine. And look what has happened to their equipment. This is what has become of Ukraine!" shouted a pro-Russian rebel fighter who identified herself by her battle name, Nursa, pointing at the remains of a Ukrainian troop transport.

Alexander, a 40-year-old businessman from Donetsk who declined to give his surname, said the Ukrainian flag had no place in the city.

"I feel this is no place for this flag. The great achievement here is that people can see it in the state that it deserves to be in," he said.

Human Rights Watch said parading the Ukrainian soldiers was a violation of humanitarian law.

Rachel Denber of the New York-based rights group cited an article of the Geneva Conventions that prohibits "outrages upon personal dignity, in particular humiliating and degrading treatment" of captives of armed conflicts.

This parade is a clear violation of that absolute prohibition, and may be considered a war crime, she said.

Resentment has grown in the east as residential areas have increasingly come under fire in recent weeks, with the civilian death toll rising to at least 2,000 since April, according to United Nations figures. In Donetsk, an estimated 300,000 of the city's population of 1 million have fled the fighting, and many of those who remain have gone weeks without electricity or running water and spent days hunkered down in bomb shelters.

Early Sunday, artillery shells struck several residential buildings as well as a hospital and morgue in downtown Donetsk, although nobody was reported killed. The government has denied that Ukraine's forces were responsible for the shelling of any residential buildings or hospitals.

The situation is even direr in Luhansk, a city closer to the Russian border whose war-reduced population of a quarter-million people has suffered under constant fighting in recent weeks. Andriy Lysenko, spokesman for the Ukrainian National Security Council, told journalists Sunday that 68 civilians had been wounded there in the past 24 hours, but could not confirm whether anyone had been killed.

Meanwhile, Ukraine has marked the 23rd anniversary of its independence from the former Soviet Union with a military parade through Kiev. An ostentatious procession of tanks and weaponry rumbled through the streets.

The Kiev procession was the first such event to be held in Ukraine since 2009, when they were outlawed by pro-Russia president Viktor Yanukovych, whose overthrow last year prompted Russia to annex the Crimean peninsula and gave rise to the separatist movement in the country's east.

In another symbolic move, Ukraine President Petro Poroshenko traveled south to the predominantly Russian-speaking port city of Odessa to give a second speech on Sunday. Ukrainian television showed footage of navy ships bobbing by the shore on a stormy, turbulent sea. Ukraine lost much of its coastline when the Black Sea peninsula of Crimea was annexed by Russia in March, and the loyalty of local authorities in Odessa to Kiev has been a top priority for the new government.

Poroshenko said Sunday that Ukraine would increase military spending by $3 billion by 2017. The Ukrainian defense ministry says its existing 2014 budget is $1.5 billion.

Ukraine's military has pleaded for more resources to oust pro-Russian rebels from their two remaining major strongholds of Donetsk and Luhansk. The BBC had reported that some Ukrainians had criticized the military parade as an inappropriate waste of money due to the ongoing bloodshed in the country's east.

Lysenko said Sunday that 722 members of Ukraine's armed forces have died in the fighting, with five killed and eight wounded in the past day alone.

The events took place one day after German Chancellor Angela Merkel called for fresh talks to resolve the crisis during a visit to Kiev.

Merkel has emerged as the West's key intermediary in the crisis due to her closeness with Russian President Vladimir Putin. Among other attributes, Merkel speaks fluent Russian as a consequence of her being born and educated in the former East Germany.

On Saturday, both Merkel and Poroshenko attempted to tamp down criticism from some Ukrainians who claimed that Merkel had not demanded enough from Moscow.

The German leader said Saturday that stopping the transfer of weapons and fighters to the rebels from across the border with Russia was a prerequisite for peace. Russia has been widely accused of providing arms, training, and funding to the separatists, a charge it has repeatedly denied.

However, Merkel also said she would not seek new sanctions against Russia despite international anger over a Russian convoy that was purportedly sent to distribute aid to war-torn areas of eastern Ukraine. A military spokesman for the Kiev government claimed that some of the trucks had picked up military equipment. On Saturday, the Organization for Security and Cooperation in Europe said that all 227 trucks had returned to Russian territory.

Poroshenko and Putin are set to meet Tuesday in Minsk, Belarus, alongside other European Union leaders. The two leaders have not met since early June and many hope that the talks could help defuse the conflict in east Ukraine.

But Merkel on Sunday cautioned against expectations of a decisive breakthrough at the much-anticipated meeting.

"The meeting in Minsk certainly won't yet bring the breakthrough," she said. "But you have to speak to one another if you want to find solutions."

NATO also accused Russia over the weekend of firing its artillery on Ukrainian forces from both its side of the border and from within Ukraine. Russia's foreign affairs ministry responded by calling the charge "unfounded."

The Associated Press contributed to this report. 

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