Dozens of Ukrainian prisoners of war were paraded at the scene of a deadly trolleybus attack that killed at least eight civilians in Donetsk.

Rebel leader Alexander Zakharchenko promised enraged local residents the opportunity to confront captured Ukrainian servicemen.

The men were forced to kneel on the ground near the bus stop while locals threw eggs, snowballs and glass at them, some of it from the shattered bus.

Women punched some of the Ukrainians, asking them why they had come to the Donbass - the region where Donetsk is located. A handcuffed prisoner introduced to the crowd as a "Ukrainian colonel" was shouted at and punched and beaten by civilians near the shelled trolleybus.

People were heard screaming "A curse on you!", "We should not even spare ropes on them!" and "Let me kill him. Let me bite off his ear!"

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Prisoners of war from the Ukrainian armed forces are escorted by members of the armed forces of the self-proclaimed Donetsk People's Republic, as they visit the bus stopAlexander Ermochenko/Reuters
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A woman makes the POWs kneel down on the ground at a site near the bus stopAlexander Ermochenko/Reuters
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Captive Ukrainian soldiers kneel in front of Alexander Zakharchenko, the leader of the self-declared Donetsk People's RepublicAleksander Gayuk/AFP

An artillery shell or mortar struck the bus stop in the rebel-controlled Donetsk in eastern Ukraine during the morning.

Rebels blame the Ukrainian side for shelling a residential area, while Ukrainian Prime Minister Arseny Yatseniuk said it was the work of separatists and that Russia bears responsibility for it.

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People look at a city bus was hit by an artillery shell in DonetskAlexander Ermochenko/Reuters
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The interior of the damaged trolleybus in DonetskAlexander Ermochenko/Reuters

Nato has detected signs of heightened Russian involvement in fighting in parts of eastern Ukraine, the alliance's top military commander said.

US Air Force General Philip Breedlove, Nato's supreme allied commander in Europe, said fighting in the pro-Russian separatist uprising was now more intense in some places than it was before September's Minsk ceasefire agreement.

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People living near the bus stop lean out of their windows to look at a Grad multiple rocket launcher system of the armed forces of the separatist self-proclaimed Donetsk People's RepublicAlexander Ermochenko/Reuters
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Members of the armed forces of the separatist self-proclaimed Donetsk People's Republic drive a tank on the outskirts of DonetskAlexander Ermochenko/Reuters

Russia denies deploying troops in eastern Ukraine, where more than 4,800 people have been killed since a pro-Russian rebellion broke out soon after Moscow annexed Crimea in March. It also rejects accusations it is supplying arms.