KABUL — An Afghan soldier opened fire on a group of Americans at a military depot near Kabul on Wednesday, killing two and wounding another three in the latest outbreak of insider violence, US and Afghan officials said.

A statement from the US military in Afghanistan said one of the people killed had been a service member and the other a civilian. “One US service member and two US civilians also sustained wounds and are currently stable,’’ the statement said.

General Dawlat Waziri, a spokesman for the Afghan defense ministry, said the Afghan soldier opened fire on a team of coalition forces around 11 a.m. at one of the Afghan army’s largest ammunition and food depots, southwest of Kabul. US officials said the attacker was killed.

Internal attacks caused enormous strain between Americans and Afghans at its peak in 2012, when 44 such attacks caused about 15 percent of the total coalition deaths that year.

Since then, the number has dropped with the decrease in the number of coalition forces, who have drawn down to 10,000 troops.

New York Times