Six policemen have been killed by suspected Taleban insurgents in the southern Afghan province of Kandahar.
The gunmen attacked the police post in the Maiwand district in the early hours of Friday, a police official said.
In a separate incident, a US soldier was killed and an Afghan soldier wounded when their patrol came under attack in central Uruzghan province.
Militants, often claiming to be members of the Taleban, have stepped up attacks in recent months.
More than 3,000 British troops are being deployed to southern Afghanistan and Dutch troops are set to move into Uruzghan province in coming months, as Nato-led peacekeeping forces try to impose control over the volatile south.
The bodies of four of the six policemen killed in Kandahar were burned, provincial highway police chief Raz Mohammed Khan told the Associated Press.
Two burned bodies were found on the roof of the building, and another two burned bodies were found inside, Mr Khan reportedly said.
A further two policemen appear to have been shot outside the building before the militants ran off.
A Taleban spokesman confirmed the attack in a telephone call with the news agency Reuters, but said seven policemen had been killed.
The attack in which the US soldier died occurred while the soldiers were investigating a weapons cache in Dihrawud district, Uruzghan province.
The injured Afghan soldier has been transferred to hospital in the city of Kandahar for treatment.
Attacks have increased in recent months and the Taleban recently announced they had launched a spring offensive against coalition troops.
"We deeply mourn the loss of one of our soldiers," said Colonel Thomas Collins, a spokesman for the US-led coalition in Afghanistan, in a statement.
"We will continue to relentlessly pursue the enemy and help the Afghan national army bring security to the people of Afghanistan."