The Associated Press news agency quotes a coalition official as saying that two people on board the plane and one on the ground were killed, and eight people were injured.
RFE/RL's Radio Free Afghanistan reported that one of the victims was a child.
A spokesman for the Canadian military, Major Quentin Innis, said that the Russian-made plane crashed after trying to avoid a truck on the runway while landing at the airport in Lashkargar, the capital of Afghanistan's Helmand Province.
Innis said the plane was carrying a team from the U.S. State Department's Bureau of International Narcotics and Law Enforcement Affairs, which has been involved in an opium eradication campaign in southern Afghanistan.
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