Police spokesman Fareed Ahmed Obaid said Taliban gunmen completely overran a checkpoint in the Mouskallah district of Hilmand province, killing three officers and wounding another two.
A second police official, speaking on condition of anonymity, put the death toll even higher, saying that five officers were killed and another two remained missing.
Afghan police are dying in unprecedented numbers as they come under attack from the Taliban-led insurgents who have been testing the local security forces since they took the lead in the war around 18 months ago.