Two Afghan policemen were wounded in the clashes that followed an attack by the Taliban in Kandahar province on Monday.
Dozens of suspected Taliban, armed with rockets and machine-guns, stormed the government headquarters in Reg district of southern Kandahar province, before fleeing after an hour-long firefight, officials said.
"We lost two policemen and four Taliban were killed," deputy police commander Salim Khan said. The fighters had come from neighbouring Pakistan's tribal areas, he said, without giving evidence.
However, the Taliban denied any of its fighters were killed in the clashes on Monday.
In another incident, Aljazeera reported that a Romanian soldier was killed and two wounded on Sunday when a landmine explosion hit a military convoy on a road near Kandahar town.
A new upsurge in Taliban attacks
is possible, experts have warned
The landmine was activated by the Taliban, a local official said.
Meanwhile, security experts on Monday warned of a new upsurge in Taliban attacks in Afghanistan, even as police defused a huge car bomb in a western city and six people died in a Taliban assault on an official building.
Afghan police discovered almost half a tonne of rockets, mortar rounds, land mines and dynamite wired together and packed into a Toyota car in the western city of Herat.
The incidents, late on Sunday, crowned a week of bloody violence which saw several casualties from among Taliban fighters, coalition soldiers and Afghan security forces.
Patrol under attack
Earlier in the day, two US and two Afghan soldiers were wounded when their patrol came under attack north of Deh Rahwood district in Uruzgan Province, a US military statement said. It did not say who launched the assault.
"I think there will
be a more concerted effort towards district centres, urban centres and towards the
Organisation Security Network
"I think there will be a more concerted effort towards district centres, urban centres and towards the capital itself," Nick Downie, security coordinator for the Afghanistan Non-governmental Organisation Security Network, which advises aid agencies, said.
There are 16,000 American and 2000 other foreign troops in Afghanistan. But security expert Downie said that while coalition troops were better equipped, Taliban fighters could sow fear effectively through a handful of high-profile attacks.
"The problem is that the insurgent has to do very little to be effective," he added.