In Afghanistan on Monday, six American troops were killed in what the Associated Press reports is the deadliest suicide attack on international forces there since August. The suicide bomber drove a motorcycle rigged with explosives into a joint NATO-Afghan patrol. Two Americans and an Afghan soldier were wounded.

The Taliban claimed responsibility for the attack, which took place as its fighters overran an important district in the south of Helmand province. The patrol was moving through a village near Bagram Air Base, north of Kabul, which is manned primarily by U.S. troops. (The Taliban attacked the Spanish embassy in Afghanistan’s capital city earlier this month.) From the New York Times:

The attack came as Taliban forces have continued grabbing territory across Afghanistan, dragging more American troops directly into the fight despite commanders’ continued insistence that the focus of the NATO force remains on training and advising. As the battle intensified this fall, the Obama administration even reversed plans to begin withdrawing troops this year, instead choosing to leave the 9,800-American force in Afghanistan through at least 2016.

Even away from the most intense battlegrounds in southern and eastern Afghanistan, and with the Afghan forces nominally taking the lead in the fighting, American forces have remained at risk, with at least 15 killed this year before the attack on Monday.

The head of the provincial council, Muhammad Kareem Atal, said that about 65 percent of Helmand is now under the control of the Taliban—the leadership is based across the border, in Pakistan—and that more than 2,000 security forces personnel have been killed fighting there this year.

According to the AP, most of the world’s opium is produced in Helmand. The Taliban insurgency is funded, in large part, by the opium crop.

Photo via AP Images. Contact the author of this post: brendan.oconnor@gawker.com.