A suicide car bomber which aimed to hit the Afghan army led to the killing of 13 people. The incident took place on Wednesday in the country’s capital, Kabul, and it’s the second suicide attack in two days.

Six soldiers, seven civilians and, of course, the bomber died in the blast, according to the reports of General Zahir Azimi, spokesman for the Defense Ministry. There were also about seven soldiers and at least twelve civilians wounded in the powerful explosion.

The suicide bomber hit the army mini bus carrying the soldiers with his bomb-filled vehicle and led to the killing of more soldiers and civilians just as US Defense Secretary Robert Gates came to the end of his short surprise trip to Afghanistan.

The responsibility for the attack was claimed by the Taliban through their spokesman Zabeeullah Mujahid. As the Taliban often exaggerate their estimations when it comes to dead soldiers, Mujahid said that up to 40 soldiers were killed in the attack.

"Today one of our Mujahid hero, Abdul Rahman, citizen of Khost province, rammed his explosive-filled car into an army bus and destroyed it completely," Mujahid said by phone.

The other suicide attack took place on Tuesday as a suicide car bomber targeted a NATO convoy in Kabul. The blast led to the injuring at least 22 civilians and the killing of the attacker. The Taliban claimed responsibility for that attack as well.

Though the Afghan capital is heavily guarded by thousands of Afghan and international troops, a series of suicide attacks took place over the last period. A suicide attack against a military bus in Kabul on September 29 led to the killing of at least 30 people while a similar attack on a police bus in the centre of the city in June, killing 35 people.

Approximately 140 suicide bomb attacks have been carried out this year in Afghanistan. This makes 2007 the most violent year since the formation of the US-backed government six years ago.

At least 6,100 people have perished since spring, the highest yearly death toll since the ouster of the Taliban regime in late 2001.