TOKYO (AFP) - A helicopter crash killed two men in western Japan on Friday after hitting a power line, according to media and authorities.

An "AS 332L" helicopter was travelling from a hydropower plant in Mie prefecture to a regional heliport for refuelling, but crashed in a mountainous area on the way, a police spokesman said.

The chopper touched a power line and crashed around 10.50am, according to an official at the transport ministry.

Local media said the two men on board died in the crash, although the police declined to immediately confirm the reports. The authorities would investigate the cause of the accident, officials said.

"We are studying the details of exactly what happened" to the helicopter, the Transport Ministry official told AFP.