|Four of those killed in the blast were policemen [EPA]
At least seven people have been killed and 17 others injured in a suicide attack in the northern Afghan province of Kunduz.
Sources told Al Jazeera that the explosion on Saturday took place in front of a butcher shop supplying the local police in the Bander Imam area of Kunduz city.
"The bomb rigged to a motorcycle detonated as a police vehicle was passing from the main market of the city," Muhammad Omar, the Governor of Kunduz, said.
"Four policemen and three civilians were killed and three civilians were wounded in the explosion," he said.
Afghanistan's northern provinces were until recently regarded as relatively peaceful but the Taliban has been staging attacks across the region over the past year.
Kunduz is a major transportation hub and lies along a crucial supply line for coalition forces that has been repeatedly attacked by Taliban fighters.
Fighters have repeatedly targeted the route and stepped up attacks on police and civilians in Kunduz
in an apparent attempt to destabilise local authorities.
While there was no immediate sign of a connection, the bombing came on the first anniversary of a Nato warplane attack on two fuel trucks just outside Kunduz city that killed as many as 142 people, the single largest loss of civilian lives since the 2001 US invasion of the country.
Afghan officials repeatedly warn that such incidents undermine the central government in Kabul and fuel support for its Taliban opponents.
Also Saturday, Nato announced the capture of a Taliban commander and the killing of six fighters in a raid on a rebel hide-out in the northern province of Takhar.
The attack followed a string of recent raids on Taliban leaders that aim to demoralise the Taliban and sever contacts between armed groups.
Source: Al Jazeera and agencies