The Taliban claimed responsibility for the suicide attack at Combat Outpost McClain in Muhammad Agha district of Logar province, south of the capital Kabul, which took place at around 8:00am (local time).
The blast outside the small base could be heard for several kilometres (miles), an AFP reporter in the area said, and was described as "huge" by local police chief.
Logar provincial governor Atiqullah Ludin said an Afghan carpenter who had just entered the camp through the gate was killed in the attack, while seven others -- five police and two intelligence officials -- were wounded. But Logar's health director, Mohammad Zarif Nayebkhail, told AFP up to 70 people from the surrounding area were taken to hospital with injuries from shrapnel or flying glass.
"Up to 70 wounded have been taken to the main hospital in the district -- seven of them are (Afghan) security guards of NATO, the rest are civilians," he said.
"Several of the wounded were in a serious condition." NATO's US-led International Security Assistance Force (ISAF) said that one coalition soldier was wounded.
ISAF said none of its troops were killed and it is not thought the blast breached the base's perimeter. Logar's deputy police chief Mohammad Abed described the explosion as "huge", adding it had destroyed some homes nearby.
"The suicide attacker wanted to ram his explosive-laden vehicle into the coalition forces base but he was stopped at the gate and detonated the truck outside the base," he said.