A police official says a helicopter crashed in the mountains in northeast Nepal and four people on board were killed.

Nepal Police spokesman Kamal Singh Bam says the helicopter was returning to Kathmandu when it crashed on the Yamuna Danda hill near Balefi village.

He said bodies of three men and a woman have been recovered from the crash site and police rescuers are trying to return the bodies to Kathmandu.

Other details were not known, but the areas is in the region worst hit by last month's devastating earthquake. The government and aid agencies are both using helicopters to carry relief materials to the mountainous area.