Kabul, Aug 23 (DPA) Seven Afghan troops and two Taliban militants were killed in clashes two days after nationwide assaults by the rebels aimed at disrupting the elections, officials said Sunday.

A police commander in northern Baghlan province was killed when his vehicle was struck by a roadside bomb in Baghlan Markazi district Saturday, said Jawid Basharat, spokesman for the provincial police chief.

Five other policemen accompanying him were also killed in the blast, he said.

The attack came two days after Taliban militants stormed several police posts in the same district, killing the district police chief and his bodyguard. The government said troops killed 20 Taliban fighters.

Because of Thursday's attack in the district, polling centres remained shut, according to the Afghan Independent Election Commission.

Northern Afghanistan was relatively peaceful until 2007 expect for sporadic roadside bombings. Baghlan and Kunduz were two of five provinces in the country where voting was severely hampered.

A security source in the province said the militants had erected a checkpoint on Kabul-Kandahar highway Saturday.