Taliban insurgents, including six suicide bombers, hit a series of government targets across Kandahar in southern Afghanistan today, triggering gunbattles that wounded at least 24 people.
The attack cast doubt on how successful the US-led coalition has been in its early year-long military campaign to restore security and bring stability to the former Taliban stronghold.
The attack started around midday and gunfire was still ringing through Kandahar more than five hours later as military helicopters fired from overhead.
Taliban spokesman Qari Yousef Ahmadi said more than 100 militants have flooded the city, including men freed in a bold prison break last month.
The attacks started with an explosion near the provincial governor's compound in the heart of the city and several other blasts were later heard in other areas in what appeared to be coordinated attacks.
"The Taliban are attacking the governor's compound and the fighting is still ongoing," Zalmay Ayoubi, spokesman for Kandahar governor Tooryalai Wesa, said from inside the heavily guarded compound.
He said six suicide bombers had detonated their explosives at several government targets across the city, including a compound belonging to the intelligence service, a foreign special forces base and Afghan police checkpoints.
A spokesman for the Nato-led International Security Assistance Force in Kabul said ISAF forces were providing security in Kandahar in a "supportive" role to Afghan forces.
Kandahar, the birthplace of the Taliban, has been the focus of military operations over the past year. US and Nato commanders have said they have made some security gains, but those successes are not yet entrenched.
Violence across Afghanistan reached its worst levels in 2010 since the Taliban were overthrown in late 2001, with record casualties on all sides of the conflict.
The Taliban last week announced the start of their "spring offensive", vowing to scale up their attacks against foreign troops and Afghan government officials. Those threats were reissued after the killing of al-Qaeda leader Osama bin Laden in Pakistan.
Last month, hundreds of prisoners, mostly insurgents, escaped from a jail in Kandahar through a tunnel dug by Taliban militants, which Afghan president Hamid Karzai's spokesman described as a "disaster" for the government.