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KIEV, July 14 (Reuters) - Ukraine's defence minister said on Monday that a Ukrainian AN-26 plane, taking part in the military campaign against separatist rebels, had been shot down by a rocket which was "probably" fired from Russian territory, the presidential website said.
Crew members from the military transport plane had been in contact with the army's general staff, the minister, Colonel General Valery Heletey, was quoted as saying. They were believed to be two in number, an interior ministry adviser said.
There was no word on casualties, but a military spokesman asked by Reuters if he could confirm that everyone on board was alive, replied: "No."
The spokesman, Vladyslav Seleznyov, said a search and rescue operation was under way in the area which is close to the border with Russia, south-east of the town of Luhansk, and has been the scene of heavy fighting with rebels.
Heletey, quoted by the presidential website, said that the plane was flying at a height of 6,500 metres and therefore could not have been brought down by weapons used by the separatists.
"So the plane was brought down by another more powerful rocket weapon which was fired, probably, from the territory of the Russian Federation," he was quoted as saying.
The incident took place amid an angry exchange between Kiev and Moscow which has accused Ukrainian government forces of firing a shell over the border at the weekend and hitting a residential area and killing a Russian man and injuring a woman.
Kiev has denied their forces were responsible. (Reporting by Natalya Zinets; Writing by Richard Balmforth; Editing by Louise Ireland)