Remarkable film about Hekmatyar's mujahideen

Just watched award-winning film-maker Najibullah Quraishi's remarkable film Afghanistan: Behind Enemy Lines, shown tonight on Channel 4. At enormous personal risk, Quraishi spent two weeks with a mujahideen group from Gulbuddin Hekmatyar's Hezbe-Islami in the north-east of the country, around Baghlan and Kunduz.
Besides being the the first account from the standpoint of the insurgents of the situation in this part of Afghanistan, the film is absolutely gripping.
Quraishi somehow managed to obtain access to the mujahideen group, who spoke openly to him, almost as if the camera was not there. They talked about the Chechens, Uzbeks and Arabs that fought with them, the way they organised, the tactics they used. Quraishi kept his camera running throughout, even as he was being questioned by a suspicious fighter.
He was asked if he would take a gun in his hand and join in an ambush. "My camera is my gun", he replied in a swift and confident retort that could have saved his life.
We watched as members of the group lay in ambush, waiting for an American tank on a low-loader to pass. They missed it twice in the morning fog. They argued when bombs did not explode and then jumped with surprise when someone dialled a mobile number as a test - and the bomb exploded.
A senior figure told Quraishi that he commanded around 4,000 fighters - more in the summer when Pashtuns from the south arrived to fight. The fighters appeared to have easy and open access to the local villages. One stated that they had no problem blocking the road. Coalition forces in the area - mainly German - seldom engaged them. The fighters were confident, cocky even.
In a brilliant move, after he left the muhahideen group, Quraishi travelled the same stretch of road on which he had filmed the ambush and spoke to Afghan police about security. They told him the mujahideen were never anywhere near the road due to constant patrols. Quraishi filmed one confident policeman standing over a dead mujahid. Three days later he filmed the corpse of the policeman.
Quraishi worked with producer James Doran on the documentary. The two men go back to 2003, when Doran made the remarkable film Afghan Massacre: The convoy of death, about the 2001 murder of several thousand Taliban prisoners by troops loyal to General Abdul Rashid Dostum. According to Doran, US military personnel knew what was happening and refused to stop it. He has alleged that film exists of US forces present during the massacre, but this is strongly denied by the Pentagon.
Quraishi's film is deeply unsettling and will certainly have a major impact on public perceptions of the war in Afghanistan. I have little doubt that he will pick up an armful of awards for a courageous piece of film-making. He had to leave the mujahideen when two men arrived from Pakistan and began to ask how he had obtained permission to film. That of course is the real question here. Who is financing Hezb-Islami and its 4,000 fighters?