Militants kill Afghan police

Four Afghan policemen are now dead after militants reportedly poisoned their food before attacking them.



The police say the attack happened at a checkpoint in the Nehre Siraj district of southern Helmand province.



It comes amid attempts by the Taliban to infiltrate the security forces.



In the meantime, three police officers have been reported missing.



Their weapons and a police vehicle are also missing.



Intelligence officials say they are believed to have been working with the Taliban.



They say an investigation is underway to establish exactly what happened.