A US military source said on Wednesday that the attack, which involved an explosion near the southern gate of the base, led to a “small number of casualties.”
Bagram is located near the capital Kabul in Parwan province. It is of high significance to foreign forces operating in Afghanistan, which remains insecure in many areas despite the presence of the US-led foreign forces.
US forces have been the target of numerous attacks in Afghanistan, especially in the recent past as the Taliban militant group, which was removed from power after the US-led invasion of the country in 2001, has regained a foothold across the country.
Even ordinary Afghans are suspicious of the US military presence in Afghanistan as many blame it for the continued bloodshed and instability in their country.
Some reports say the Taliban is currently in control of nearly half of Afghanistan while some defectors of the group have joined Daesh, a Takfiri terrorist group based in the Middle East, which is using the lawlessness in some parts of Afghanistan to establish its own insurgency.
Washington has decided to increase by some 4,000 troops its current contingent of 8,500 military personnel in Afghanistan in an apparent bid to prevent a total failure of the international mission in the country.
More than 2,000 US forces have been killed and thousands more wounded since 2001.