"Six civilians were killed in a suicide attack close to the gates of Kanadahar airport today," said Kandahar police chief General Abdul Razeq.
The Taliban, the militia leading a 10-year insurgency against the Afghan government and tens of thousands of NATO troops, claimed responsibility.
Spokesman Qari Yousuf Ahmadi said the target was "the bullet-proof vehicles of foreign forces".
The army commander for southern Afghanistan, General Hamid Wardak, said earlier that three civilians died in the attack, which was "on foreign special forces at the entrance gate of Kandahar international airport".
A spokesman for NATO forces in Afghanistan said there were no casualties among foreign troops in what he called a "vehicle-born suicide attack".
The Taliban, toppled in late 2001 in a US-led invasion, are waging an insurgency against the government and US-led forces, who have some 130,000 troops in the impoverished and war-ravaged country.
The hardliners announced earlier this month that they planned to set up a political office in Qatar, widely seen as a move towards peace negotiations with Washington and its Western allies.
A key US demand for any progress in negotiations is that the Taliban abandon violence and break with Al-Qaeda and other "terrorist" groups.
Kandahar is the spiritual capital of the Taliban and southern Afghanistan is a key battleground that continues to see persistent violence despite a surge of US troops in 2010 and 2011.
In neighbouring Helmand province on Wednesday, two attacks just hours apart killed 16 people and wounded more than 20 others.
A suicide bomber on a motorcycle killed 10 civilians and two policemen in the first attack at a bazaar, while an intelligence official was among the dead in a second blast caused by a mine, which was claimed by the Taliban.
General John Allen, commander of NATO`s International Security Assistance Force, said that those attacks showed that "(Taliban leader) Mullah Omar has lost all control over Taliban insurgents".
"Otherwise he would immediately denounce these attacks and order his `forces` to stop attacking innocent Afghan civilians," Allen said.
"This latest act of violence further confirms that the insurgency has declared outright war on the people of Afghanistan and will stop at nothing to continue to use terrorism and intimidation to advance their own malign and selfish ends." (H-AK)
Editor: Ella Syafputri
Copyright © ANTARA 2012
