At least eight people - six Afghan policemen and two civilians - have been killed in two bomb explosions in Afghanistan, police say.
Police are currently in the firing line
The policemen were killed in the eastern province of Khost, when a roadside bomb detonated near their vehicle patrolling with foreign forces.
There are no reports of any casualties among soldiers in the convoy.
Two civilians were killed when their vehicle was bombed in neighbouring Paktika province, Nato officials say.
'Tip of the spear'
Correspondents say this year the south and east of Afghanistan have seen the worst violence since 2001.
The police said additional troops had been sent to the area of the Khost attack for search operations.
Neither Nato nor US-led military forces have commented on the Khost attack, and it is not clear to which organisation the foreign troops belonged.
Reports quoted a Taleban spokesman as saying they were responsible for the attack.
The BBC's Charles Haviland in Kabul says that both Khost and Paktika share long borders with Pakistan and both have been hit hard by insurgency-related violence.
The police have suffered many casualties recently, as violence across the country has intensified.
On Tuesday, 17 people, including 12 schoolchildren, were killed in a suicide bombing in south Afghanistan.
At a press conference, the outgoing head of the section of the coalition which is training the Afghan security forces described the police as the "tip of the spear" in protecting the country's people, with a presence in every village.
Maj-Gen Robert E Durbin said the force still only had 40% of the required equipment such as vehicles and weapons, and that it was underpaid compared with the army.
But he said these matters were being rectified and praised the quality of people joining the security forces.