More than 800 Taliban insurgents have launched a major offensive in southern Afghanistan to try to gain territory recently vacated by US troops, officials said on Wednesday, with 40 civilians killed in five days of fighting.
About 100 Taliban have been killed, according to the interior ministry, in clashes that erupted as Afghanistan wrestled with a political crisis over alleged fraud in the June 14 election to choose a successor to President Hamid Karzai.
The assault highlights the challenges facing Afghan security forces battling the Taliban as US-led NATO forces pull out.
Local officials in Helmand province said that 800 militants were involved in attacks centred on the Sangin district of Helmand province, a hotbed of fighting during the 13-year insurgency.
The last US troops pulled out of Sangin only last month, handing over their remaining bases to Afghan soldiers and police who have now taken on full responsibility for fighting the militants.
"About 800 fighters started to storm four districts of Helmand last Thursday night," Helmand provincial governor spokesman Omar Zwak told AFP.
"At least 21 Afghan forces have died and close to 40 civilians were killed."
A government official in Kabul confirmed the figure of 800 Taliban fighters.
Zwak said reinforcements had been sent to repel the attacks in Sangin, Nowzad, Kajaki and Musa Qala districts, where 2,000 families have fled the violence.
The threat of a Taliban revival as NATO combat troops withdraw after more than a decade of war is a major fear for many Afghans, though government and NATO officials insist that the national army and police are increasingly effective.
On Wednesday, the interior ministry confirmed the scale of the fighting in Helmand but insisted that the insurgents were being beaten back.
"There was a major attack by the Taliban and their supporters," ministry spokesman Siddiq Siddiqi told AFP. "We have reports of a lot of enemy attackers over the last few days.
"We are reinforcing Afghan national security forces and have suffered no major loss of territory. About 100 Taliban have been killed so far."
Siddiqi said that 18 policemen were killed on Tuesday.
Power knocked out
Local officials said the Taliban had launched overnight attacks on police checkpoints, and that power from the Kajaki dam to Lashkar Gah, the capital of Helmand, and to Kandahar city had been cut, causing long outages.
Haji Akhtar Mohammad, an elder in Sangin, told AFP that the insurgents had placed improvised explosive devices (IEDs) in villages and along roads used to transport supplies to Afghan government forces.
He added that civilians were running short of food due to the fighting.
Afghan politicians remain locked in a dispute over the ongoing election vote count, with presidential candidate Abdullah Abdullah alleging massive fraud by his poll rival Ashraf Ghani, the election authorities and outgoing President Karzai.
On Tuesday, the UN said it had stepped in to help broker an end to the stand-off, hosting talks between Abdullah and the Independent Election Commission.
According to reports, Ghani has made a surprise comeback and is ahead in the vote count after finishing well behind Abdullah in the first-round election on April 5.
Foreign diplomats have expressed alarm at the prospect of a disputed outcome that could trigger a spiral of instability as the NATO combat mission wraps up this year.
The preliminary election result is due on July 2 and the final result, after adjudication of complaints, is scheduled for July 22.