KANDAHAR, September 11, 2008 (AFP) - A suicide car bomb blew up near a convoy of private security guards in Afghanistan's southern city of Kandahar Thursday, killing two Afghan civilian passers-by, a governor's spokesman said.

There was no immediate claim of responsibility for the blast but it was similar to scores carried out by the Taliban, who were removed from government in a US-led invasion launched after the September 11, 2001 attacks.

'There was a suicide car bomb attack against one vehicle of a private security company of a construction company in Kandahar city,' provincial government spokesman Zalmai Ayobi told AFP.

'Two civilians were killed and six were wounded,' he said.

A witness said that one of the dead was a boy on his way to school and the other was an adult male.

Ayobi said the attack was against a convoy of Afghan guards from a security company but the targeted vehicle appeared to have driven off.

'The suicide attacker tried to ram his vehicle into the convoy of the private security company but the vehicles seem to have driven away,' he said.

Canadian troops immediately sealed off the area as ambulances rushed the wounded to hospital, an AFP reporter at the scene said.

The bomb blew a crater in the road and parts of the vehicle used in the attack littered the scene, along with bits of the attacker's flesh.

It was the second attack in the tense city since Sunday when two suicide bombers blew themselves up inside the provincial police headquarters, killing five people and wounding nearly 40.

The Taliban, which took up arms in Kandahar province before sweeping to power in the 1990s, claimed responsibility for the police blasts.

Taliban rebels have carried out scores of suicide bombings as part of a growing insurgency launched soon after they were removed from government in a US-led invasion in late 2001.

In one of the most audacious attacks, they used suicide bombers to blow open Kandahar jail in June, enabling more than 1,000 prisoners -- about half of them militants -- to escape.

The suicide attacks on the New York and Washington exactly seven years ago prompted the invasion that drove the Taliban from government in late 2001 for harbouring Al-Qaeda leaders.

Despite the efforts of international troops and a growing number of Afghan security forces, extremist insurgents have been able to increase their attacks -- most often bombings -- claiming thousands of lives.