KABUL (Reuters) -- A suicide car bomber has blown himself up near a U.S. military base in the Afghan capital, wounding six civilians, an Afghan security official said.
Violence across Afghanistan last year reached its worst levels since the war began in late 2001, despite significant increases in foreign troops. The latest attack came little more than a week after brazen assaults in Kabul killed five people.
The suicide bomber struck on a road leading east from the city center near the main entrance to Camp Phoenix, a base used mainly by U.S. forces.
Abdulghaffar Sayedzadah, a spokesman for Kabul's criminal investigation department, said six Afghan civilians were wounded. Most had been working nearby, he said, but could not confirm if the base was the attacker's intended target.
U.S. and NATO-led forces said they were investigating an explosion outside the main gate of Camp Phoenix and initial reports indicated the cause of the explosion was a car bomb.
A man describing himself as a Taliban spokesman, Zabihullah Mujahid, said in a text message to Reuters the attacker was a member of the Islamist group and had been in a car.
Mujahid said the target had been a convoy of foreign troops.
U.S. soldiers were blocking access to the scene on the Jalalabad road, the main highway leading east out of the capital. An Afghan soldier at the scene told Reuters a suicide bomber had blown himself up as a U.S. military convoy drove by.
Taliban insurgents have spread their attacks out of traditional strongholds in the south and east into previously peaceful areas.
Militants have carried out an increasing number of attacks inside the capital, with suicide bombings and commando-style attacks aimed at both military and diplomatic targets.
On January 18, Taliban gunmen launched an audacious assault in the centre of the city with suicide bombers blowing themselves up at several locations and militants battling security forces from inside a shopping centre engulfed in flames.
A car bomb exploded near a NATO convoy outside Camp Phoenix in mid-November 2009, injuring nine foreign soldiers as well as several civilian contractors and Afghan bystanders.