A security official based in the province identified the slain officer as Lt. Col. Abdul Basir Nuristani, chief of staff to the 3rd ANA brigade.
The source, speaking on condition of anonymity, said Nuristani was killed in Bala Murghab district on Sunday evening when the mortar shell hit a military camp there.
Naeemuddin Burhani, the governor’s spokesman, confirmed the killing of Nuristan. Several security guards of the ANA official were injured, he said.
Elsewhere, one ANA soldier was killed and four others were wounded when unidentified motorcyclists opened fire at a pick-up in the 12th police district of Herat City, said police spokesman Abdul Ahad Walizada.
Dr. Ibrahim Mohammadi, head of the Herat ambulance service, said the victims were evacuated to civil hospital.
There was no immediate claim of responsibility for the attack.