A suicide car bomb struck near a military base in Afghanistan's Khost province on Monday, Afghan news agency Khaama Press reported.
The Afghan interior ministry confirmed that a car bomb went off near a military base at around 1pm local time.
The incident came as US Defense Secretary Jim Mattis arrived in Afghanistan on an unannounced visit Monday, an American defence official confirmed, hours after his Afghan counterpart resigned over a deadly Taliban attack.
Mattis, making his first visit to Afghanistan as Pentagon chief, was due to meet top officials including President Ashraf Ghani less than two weeks after the US dropped its largest non-nuclear bomb on militant Islamic State (IS) hideouts in the country's east.
