A suicide bomber blew himself up in a crowded bazaar in southern Afghanistan on Sunday, killing 24 people, police said, in the latest in a series of Taliban-style attacks.
The blast in Uruzgan province came as Afghan and international security forces battled Taliban-led insurgents in northeastern Afghanistan, with the NATO-led force reportedly suffering some casualties.
The attacker rammed a bomb-filled vehicle into a police van in the bazaar in the Deh Rawood area, 400 kilometres (250 miles) southwest of Kabul, causing an explosion that ripped through several shops, officials and a witness said.
Twenty civilians and four policemen were killed, said Uruzgan police chief Juma Gul Hemat.
"In the hospital we have 27 people wounded," he said.
He said the explosives were packed into a three-wheeled vehicle, but the interior ministry said in a statement that they were attached to a motorbike.
The bomb exploded in the centre of the bazaar, said one shopkeeper who gave his name only as Fazlullah.
"It was very crowded when the bombing took place. Most of the casualties are shopkeepers and people and children who were selling stuff on the roadside," he said.
"Around 15 shops have been damaged. I saw lots of people killed and injured. I can see human flesh, blood and pieces of metal, wood, clothing scattered around. Everything is bloodied," he told AFP by telephone.
Provincial health chief Khan Agha Miakhail told AFP that 31 wounded people were taken to the main hospital. They included four children under the age of 10, he said.
There was no immediate claim of responsibility for the bombing but similar attacks have been carried out by Taliban militants, who have led an insurgency against the Kabul government since being ousted from power in 2001.
The blast came less than a week after a suicide bombing at the Indian embassy in the Afghan capital Kabul, which killed more than 40 people including four Indian nationals, two of them senior diplomats.
The Kabul bombing was the deadliest suicide attack in the capital since the 2001 fall of the Taliban.
Nearly 70,000 international soldiers are deployed in Afghanistan to help the government fight the insurgency, but the violence has only escalated, with the insurgents making heavy use of suicide attacks.
NATO-led soldiers were meanwhile engaged in heavy battles in the northeastern province of Kunar on Sunday, where they had suffered casualties after being attacked by militants, officials said.
"The fighting started early on Sunday and it's still ongoing. We have taken casualties," said Captain Mike Finney, a spokesman for the NATO-led International Security Assistance Force.
He could not immediately give further details.
The deputy provincial governor of adjoining Nuristan province, Abdul Aleem, said the clashes started with an attack on an ISAF base.
The troops had responded with air strikes, he said.
"Some homes were destroyed and damaged. There have been casualties among all three sides -- the locals, Taliban and foreign forces," he said.
Four police were meanwhile missing after days of clashes with insurgents in a district of Nuristan on the border with Pakistan, Aleem said.
Insurgents had overrun two police posts in Bargi Matal district, he said. Two of the insurgents, whom Afghan officials said had attacked bases in Pakistan, were also killed, Aleem said.
The Taliban-led insurgency, which Afghan officials say has key support from militant bases in Pakistan, has grown deadlier every year since it was launched.
About 8,000 people died in insurgency-linked violence last year, many of them insurgents. But more than 1,000 of them were civilians.