Officials in Paktika province said an improvised explosive device had killed six officers on Sunday.
Witnesses in Kunar province said some soldiers were wounded in the roadside explosion in the Manogai district.
A Taliban spokesman said three foreign soldiers died in the blast.
Nato denial
However, officials with Nato's international security assistance force and the US-led coalition said none of their troops were hurt.
Nato and the coalition have nearly 50,000 troops in Afghanistan.
Ousted from government by US-led forces in 2001, the Taliban says it has trained hundreds of suicide bombers to carry out attacks.
A British soldier was killed early on Saturday during a mission to clear a Taliban compound on the outskirts of Garmsir in Helmand province.
Nato said last week that 85 people, including 40 civilians, had been killed during the first 23 days of May by improvised explosive devices, a favourite tactic of the Taliban.