An Mi-28 military helicopter crashed in an uninhabited area of southwestern Russia, killing the crew, two Russian news agencies said Thursday.
"An Mi-28 crashed in the Kaluga region... the crew died," the TASS news agency said, quoting a source in the defence ministry.
"According to preliminary information, a technical malfunction caused the disaster," the Interfax news agency said, citing a defence ministry statement.
It crashed in a forest about 150 kilometres (93 miles) from the Ukrainian border, a local official told TASS.
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