District police chief Amanullah, who goes by only one name, said Saturday eight others were wounded in the previous night's attack in Nawa district, AP reported.
Qari Yusouf Ahmadi, Taliban spokesman, claimed responsibility for the attack. In a statement sent to media he said fighters overran three checkpoints, killing around 15 local forces.
Separately, gunmen killed a district judge in western Herat province, said Iqbal Nezami, spokesman for the provincial police in Ghor province.
Nezami said Mawlavi Baz Mohammad was on his way from Ghor to Herat when gunmen forced him from his vehicle and killed him in Shandand district.
No one claimed responsibility.