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Roadside bomb explosions in southern Afghanistan have killed at least five civilians and five policemen. The attack came as NATO’s new Secretary General visited Kabul   (discuss) with Afghan officials and candidates ahead of the August 20   (president) election.
Afghan officials in southern Helmans province said a group of civilians (travel) to a wedding party when  big vehicle, which was being pulled by a tractor, hit a roadside bomb.
Officials have blamed Taliban insurgents（叛乱分子）as part of efforts to discourage voters  taking part in the coming election.
Five policemen were also killed in a separate roadside bomb burst in Helmand,  region is a known Taliban stronghold（据点） thousands of US Marines and British soldiers are engaged major anti-insurgency operations to improve securityAfghans go to vote.
The security situation deteriorating（恶化）in southern parts of the country has been a cause of concern for both Afghan election officials and international observers since the (remove) of the Taliban from power in 2001.