A bomb blamed on insurgents blew up a civilian minivan in southern Afghanistan on Monday and killed four men while an Afghan soldier died elsewhere in a separate blast in the east, authorities said.
Three more civilians were wounded in the explosion in the southern province of Zabul, deputy provincial police chief Ghulam Jailani Khan told AFP.
The bomb had been planted to target security forces by the "enemies of Afghanistan", Khan said, using a term referring to insurgents linked to the Taliban, who were in government until late 2001.
Another bomb exploded near the eastern town of Khost on Monday, killing an Afghan soldier who was on patrol, an army official told AFP.
Roadside bombs are the main Taliban weapon in a dragging insurgency that has led Afghanistan's allies to deploy around 70,000 troops here to defeat extremists described as an international threat.
The Afghan intelligence agency said three militants were also killed in the eastern province of Paktika on Monday when a bomb exploded as they were planting it into a road.
And the defence ministry said troops killed three "terrorists" in southern Helmand province, an insurgent hotspot.
A woman and a child were wounded in the operation on Sunday in the Nad Ali district, the US military said, confirming that three men were killed.
Four others were arrested, it said. Helmand is a Taliban stronghold and the main producer of Afghanistan's opium crop which is used to make heroin.
The operation was in the same area where security forces said a four-day operation last week killed 60 militants and uncovered and destroyed 92 tonnes of narcotics as well as drug-processing chemicals and explosives.
It was the largest drugs cache seized by Afghan-led forces, the military said.
The Taliban are waging an insurgency that officials say is funded in part by drugs money.