Taleban guerrillas attacked a convoy of provincial officials and police in southern Afghanistan and 11 Taliban and three policemen were killed, the government said on Tuesday.
In a separate incident, four Afghan aid workers were killed in a roadside blast west of Kabul, police said.
The attacks come after several days of some of the heaviest Taliban attacks since they were ousted in 2001 and just as Nato is bringing thousands of extra troops into the country.
More than 250 people have been killed since last Wednesday - more than the number reported killed in Iraq during the same period - according to figures from the US military and Afghan authorities.
The government convoy, which included the provincial police chief, was travelling in the north of Helmand when it came under attack late on Monday, a provincial official said.
"Three policemen were martyred and six were wounded," said Interior Ministry spokesman Yousuf Stanizai. Eleven Talbian were killed in subsequent fighting, his ministry said.
A Taleban spokesman, Qari Mohammad Yousuf, claimed responsibility for the attack and said there were no Taleban casualties.