A suspected suicide bomber has attacked a market in the eastern Afghan city of Gardez, killing at least nine people.
The dead included four young children. Police say 28 others were wounded, some seriously.
A BBC correspondent in Kabul says the target appears to have been the commander of a private security firm working for American forces.
The man, his brother, and two bodyguards were killed. Many civilians were also caught in the blast.
Gardez is the capital of Paktia province, and Thursday's attack happened at 1630 local time (1200 GMT) when the suspected suicide bomber, wearing an explosives-filled vest, detonated his device.
"This was a suicide attack," said the spokesman for the governor of Paktia province, Rohullah Samon.
The BBC's Mark Dummett in Kabul says the Taliban regularly target senior government and security officials in Afghanistan's south and east along the Pakistan border, where the insurgency is at its strongest.
Earlier on Thursday the governor of neighbouring Khost province was injured after a bomb was detonated just outside his office.
It is not the first time Gardez has been targeted.
In December, Taliban militants seized a building near a police station and in the ensuing firefight two militants were killed and a number of police officers and civilians injured.