A Taliban car bomber has hit a NATO military convoy in Kabul, killing 17 people, including 13 US troops, in the deadliest attack in Afghanistan in months.

    The interior ministry said three bystanders and a policeman were killed, while NATO's alliance force said at least 13 Western military forces died and US officials confirmed they were all American.

Civilian victim of Air Force GBU 31's in August 2011
"Initial reports indicate that 13 International Security Assistance Force (ISAF) service members died following an improvised explosive device attack in Kabul earlier today," the force said in a statement.

Thick black smoke could be seen rising from an fire still raging at the scene, cordoned off by Afghan and
 ISAF soldiers, while fire hoses were putting out another blaze nearby, footage on private television channel Tolo showed.

    NATO's coalition forces were seen carrying the charred bodies of some of those killed away on stretchers from the wreckage of the bombed bus.

    "It was a huge explosion - I saw at least 10 bodies of foreign forces taken out of their capsized bus and evacuated by two helicopters," one witness told AFP at the scene.

    Half a kilometre from the explosion, shattered windows and scattered pieces of twisted metal showed the scale of the massive blast.

    It was the deadliest incident in the more than 10-year war since the Taliban apparently shot down a US helicopter in August, killing 30 American troops.

As in any war, Taliban weapons becoming more sophisticated
That attack marked the biggest single loss of life for American and NATO forces since the US-led invasion of Afghanistan toppled the Taliban in late 2001, shortly after the September 11 attacks in the United States.

At Kabul's Estiqlal hospital, 10 people had been brought in for treatment, but one policeman and one woman had since died of their injuries, said the head of the hospital Mohammad Ali Eshan.

    One of the injured, 30-year-old Abdullah, who like many Afghans goes by just one name, had hurt his hands and face in the attack.

    "I was driving my motorcycle, a convoy of foreign forces had stopped around 100 metres away. I suddenly heard a loud explosion and was knocked down," he said. "When I opened my eyes I was in hospital."

  The Taliban, fighting Afghan and Western forces to regain control of Afghanistan after a decade of bloody insurgency, claimed responsibility for the attack.

Leadership of U.S. forces create new Taliban every day
"A suicide car bomb attack was carried out on a bus of foreign forces in the Dar-ul-Aman area of Kabul," said Taliban spokesman Zabiullah Mujahid in a text message sent to AFP.

At around the same time in the eastern city of Asadabad in Kunar province, a female suicide bomber blew herself up outside a local branch of Afghanistan's spy agency, a spokesman for the Kunar provincial governor said.

   The woman struck outside the local operations centre for the National Directorate of Security (NDS), said spokesman Wasifullah Wasifi.

    "As a result of the explosion two guards of the operative directorate were wounded," he said.The attacks come a day after the Taliban launched a four-hour long assault on a US-run civilian-military base and NDS local branch in the southern city of Kandahar, the spiritual birthplace of the insurgent movement.

    Earlier in the week it was announced in Kabul that Afghan President Hamid Karzai would next week give a list of areas in up to 17 provinces that will soon see a handover from NATO to Afghan control as Western governments begin to bring troops home, with the overall combat mission due to end in 2014.

    A regional conference is to be held in Istanbul next week as international backers of Karzai's government push talks with the Taliban aimed at finding peaceable resolution to the long war.