Nato helicopter crashes in Afghanistan.

A Nato helicopter has crashed in south-western Afghanistan, with four people on board, according to BBC.

It is not clear whether anyone on board the Black Hawk helicopter has survived.

The official said that enemy action could not be ruled out, but initial indications were that the weather was to blame.

No British forces were involved, according to the UK Ministry of Defense.

Those on board are believed to be American.

Isaf military officials in Kabul have told the BBC that the crash site is secure and the cause is under investigation.

The crash occurred in what Nato terms the South West Region of Afghanistan, which includes the provinces of Nimruz and Helmand.