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KIEV, Aug 1 (Reuters) - Ukrainian television said on Friday 20 servicemen had been killed in an attack by pro-Russian separatists in east Ukraine during the night, but a military source said the death toll was likely to be lower.
Military officials said a paratrooper unit had come under mortar and tank fire near the town of Shakhtarsk, in the region where a Malaysian airliner was brought down on July 17, and the number of casualties was being checked.
Channel 112 gave no details but said in a morning news bulletin: "Twenty Ukrainian paratroopers were killed in a Grad missile attack near Shakhtarsk."
Ukrainian government forces have intensified their military offensive against the rebels in mainly Russian-speaking eastern Ukraine since the airliner came down, killing 298 people. The separatists are now pegged back in their two main strongholds, the cities of Donetsk and Luhansk.
The United States says the separatists probably shot down the plane by mistake with equipment provided by Russia, but the rebels and Moscow deny the accusation and blame the crash on Kiev's military campaign to quell the uprising.
Kiev said its latest combat report that Russian aircraft had flown over east Ukrainian territory, the latest of several such accusations in the last few weeks, but Moscow has denied such reports.
The United Nations said in a report this week that more than 1,100 people had been killed and nearly 3,500 wounded between mid-April and July 26. (Reporting by Pavel Polityuk, Editing by Timothy Heritage)