Two suicide bombers targeted a community meeting at a major border town in southern Afghanistan, killing at least four people and wounding 15 others, local officials said on Sunday.
The meeting of tribal elders, known as a shura in Afghanistan, was being held around noon local time when a man drove a car near the compound and detonated a powerful bomb.
"Part of the roof where the elders were fell down after a suicide bomber struck the meeting," said Sayed Hashem Agha, the governor of the Spin Boldak district, Kandahar province.
Minutes later, a man strapped with explosives ran towards a group of police guarding the compound. They fired at him, causing the bomb to detonate.
There was no immediate claim of responsibility for the attack, which happened as Afghan President Hamid Karzai was preparing to visit Washington for talks with President Barack Obama over the future of the country once NATO pulls out most of its troops by the end of 2014.
Spin Boldak is the country's second busiest border point on Afghanistan's porous long frontier with Pakistan, and is considered an important smuggling route between the two countries. Numerous insurgent attacks have taken place there.