A cargo plane carrying U.S. drug enforcement officials overran the airstrip of an airport in southern Afghanistan, killing at least four people and injuring 13.

The crash occurred Monday as the landing plane veered to avoid a truck on the runway and slid headlong into a nearby nomad settlement of mud houses and tents, Sabawoon Online reported. Two children on the ground were killed, as well as two persons aboard the plane.

A U.S. official said the two dead on the leased Russian-made plane were Ukrainian flight crew members.

The accident happened at the Bost airport in Lashkar Gah, capital of Helmand province, about 325 miles southwest of Kabul.

At least 13 others were injured, including 11 U.S. citizens on the plane.

A Canadian military spokesman said the plane, leased by the U.S. State Department, was carrying a team from the Bureau for International Narcotics and Law Enforcement Affairs. The bureau has been helping Afghan authorities conduct large-scale opium eradication campaigns across southern Afghanistan.