In Afghanistan, six policemen have been killed and two injured as Taliban militants opened fire on them in the southern Helmand province. An Interior Ministry statement today said that a unit of police force was busy in destroying poppy farms in Nahr-e-Saraj district yesterday when militants opened fire in which the policemen were killed . Notorious for growing poppy and militancy, Helmand has been regarded as the stronghold of Taliban fighters in south Afghanistan. Some 15,000 Afghan and NATO-led troops are involved in a massive operation since February 13 to take control of Marja district, a bastion of Taliban in Helmand.