Several U.S. soldiers have been wounded and at least one Afghan soldier was killed Saturday in an incident that's being investigated as a possible "insider attack" on a military base in Afghanistan, officials confirmed to NBC News.

The incident occurred at Camp Shaheen and seven wounded soldiers have been medevaced to nearby hospitals, officials said. The base is the headquarters of the 209th Corps of the Afghan National Army and is located near the city of Mazar-e Sharif.

"We are aware of an incident that occurred at Camp Shaheen in Mazar-e Sharif at approximately 2 p.m. local time," a spokesman for Operation Resolute Support, the NATO-led mission to assist Afghan soldiers, posted in a statement on Twitter.

"At this time we can confirm there are no U.S. or NATO Resolute Support fatalities. U.S. soldiers have been wounded. One Afghan soldier was killed and one was wounded in the incident."

UPDATE: Seven U.S. service members wounded, evacuated for treatment. Insider attack Camp Shaheen, Mazar-e Sharif under investigation https://t.co/WXujMMXA3U — Resolute Support (@ResoluteSupport) June 17, 2017

Three American soldiers were killed during a joint U.S.-Afghan military operation in Nangarhar province last weekend. And in April, more than 100 Afghan soldiers were killed or injured at Camp Shaheen when Taliban fighters ambushed the military base.

The latest incident comes at a time when Trump administration is revising its Afghanistan strategy and discussing a possible troop surge in the region. Dana White, a spokesperson for the Pentagon, told NBC News that Defense Secretary James Mattis will present a revised military strategy to President Trump "in the coming weeks."

"The president has delegated force management authority for Afghanistan to the secretary," White said. "Any decisions about troop numbers will be made only after consultation with the inter-agency, the Afghan government, NATO allies and coalition partners."

This is a developing story. Please check back for updates.