KANDAHAR, Afghanistan — At least seven people were killed Wednesday in southern Afghanistan, where a Taliban suicide car bombing struck an Afghan National Army convoy, Afghan officials said. It was the first major attack since President Trump announced his strategy for Afghanistan in a speech Monday night.

Omar Zwak, a spokesman for the governor of Helmand Province, said that a car bomb exploded at the parking lot of the Police Headquarters of the provincial capital, Lashkar Gah. The target appeared to be a parked convoy of soldiers, but the explosion killed two women and a child, as well as four soldiers. Another 38 people were wounded, most of them civilians, Mr. Zwak said. The parking lot was also used by civilians visiting the Police Headquarters.