"Up to 12 armed militants were killed during a cleanup operation conducted by Afghan National Security Forces in Nad Ali and Marja districts of Helmand province over the past 24 hours," the ministry said in a statement.
The security forces also found weapons and ammunition, and defused 30 rounds of roadside bombs and landmines in Helmand during the same period, the statement added, Xinhua reported.
Helmand, notorious for poppy growing, is also a known Taliban stronghold.
Afghan security forces have pressed on clearing restive provinces of militants, as Taliban fighters have been attempting to take territory and consolidate their positions ahead of winter in the mountainous parts of the Central Asian country.
The Taliban militant group has yet to make comments.