The slain security force members were guarding the Pashdan Dam at the time of the attack.

According to Nizamuddin Khpulwak, the spokesman for National Water Affairs Regulation Authority, the attack took place around 3 am.

Four more security force members are said to have sustained injuries.

Jailani Farhad, the Herat governor's spokesman, said that the at least five Taliban insurgents were chased and killed by security force members following the attack.

The Taliban is yet to comment on the report.