Taliban seize district in eastern Afghan province
Officials in Afghanistan say insurgents allied to the Taliban have taken another district in a strategically important province in the north-east.
Nuristan Governor Jamaludin Badar told the BBC that 10 insurgents and three policemen had been killed.
Nato-led forces now say they and Afghan troops provided air support on Wednesday.
Local officials say they are trying to re-take the western district of Doab which Nato denies is in Taliban hands.
At least three districts in Nuristan are now under Taliban control. In others, the government presence is either weak or limited.
"We had intelligence reports that close to 500 Arabs, Chechen, Pakistani and Afghan fighters wanted to attack and take the districts," Mr Badar told the BBC.
"The fighting is still going on. Our weapons are no match to those of the insurgents. We have no hand grenades, mortars or heavy machine guns.
"We have asked for help from the defence ministry but they have not responded to us."
The insurgents control key routes into the provincial capital, Parun, allowing them to impose a blockade on the city.
Nuristan is a remote mountainous region and communications are poor. There are concerns that the blockade could mean food shortages for the local population but that is hard to confirm.
The central government did recently promise military reinforcements but the sense within Afghanistan is that Nuristan has inadequate security forces and is not getting the help it needs.
It is not traditionally a stronghold for the Afghan Taliban. But it does have a history of tribal extremism and militancy.
Nuristan borders Pakistan's tribal areas and there seem to be growing alliances between local leaders and Pakistani Taliban groups.
That makes Nuristan strategically important in the wider conflict as an entry point into Afghanistan - and a potential haven for Pakistani militants.
It also shares an interior border with Kunar province to the south. That too lies along the border with Pakistan and is important in the battle against the insurgents.
The United States has invested heavily in building infrastructure in Kunar and will be keen to protect it.
Nuristan is hard to defend and has not so far been a priority for the central government.
Afghan intelligence officials in Nuristan say that they have repeatedly warned the government and Nato about the worsening security situation.
"If you don't come and deal with this mess. You will be dealing with another Waziristan and al-Qaeda's next home inside Afghanistan," one official told the BBC.