Three U.S. soldiers were killed and one other was injured when, the U.S. military said, an Afghan soldier opened fire in the Achin district of Afghanistan's Nangahar province in a similar attack last Saturday.
North Atlantic Treaty Organisation said an investigation into the incident has been launched. Dillon C. Baldridge, 22 of Youngsville, North Carolina - were killed June 10 when an Afghan soldier opened fire on them in Peka Valley, located in Nangarhar Province. Another Afghan soldier was also wounded.
"On my way here I was informed that US service members were killed and wounded in an attack in Afghanistan", Pence said. "Initial information shows three USA soldiers visiting the base were wounded", Mohammad Radmanish, a spokesman for the Afghan Defense Ministry said. There were no US fatalities.
In April, Taliban gunmen and suicide bombers attacked the same sprawling Afghan army training base, leaving at least 100 Afghan soldiers dead and scores more wounded.
Defense Secretary Jim Mattis said this week that he will present a new USA military strategy for Afghanistan, along with adjusted troop numbers, in the coming weeks to President Donald Trump. "More information will be provided as it becomes available".
American military commanders in Afghanistan have requested thousands of additional boots on the ground to boost the North Atlantic Treaty Organisation troop presence in the country.