As many as 15,000 US, British and Afghan soldiers have launched a massive military offensive in Afghanistan.
Helicopter borne attack troops are battling for control of the Taliban held areas of Marjah and Nad Ali in Helmand province.
As night fell more than 4,000 US marines supported by the Afghan army moved into the area as part of Operation Moshtarak.
The long anticipated attack is an attempt to re-establish government control and undermine the Taliban in their heartland.
According to reports there appears to be little sign of the Taliban or local civilians.
Prior to the assault NATO forces distributed leaflets in the area warning of the planned offensive in order to minimise the number of civilian casualties. The message to the Taliban was clear, leave the area or face death.
The thousands fleeing the fighting are heading for the capital of Helmand, Lashkar Gah.
The offensive is the biggest undertaken in Afghanistan since the overthrow of the Taliban in 2001.