A police officer L/Cpl. Alhassan Asare has been found dead in Akyem Swedru in the Eastern region.
A police situation report said he was found lifeless in a plastic chair while on guard duty at the Dukes Petroleum Filling station at about 5:40 am Tuesday.
His rifle was in between his thighs having sustained severe gunshot wounds on the head. The uniform was soaked with blood.
Three empty shells were found on the ground, the report said.
This comes 24hours after an officer was killed in Manso Nkwanta in the Ashanti region.
A policewoman, General Corporal Agatha Nana Nabin was on July 30 killed while on snap check duties at Kumbungu in the Northern region.
She was shot at the back of the head with the bullet passing through the mouth and killing her instantly, media reports say.
It brings to three, the number of police officers murdered in the past 21 days.
A police statement said the IGP has ordered specialised teams to investigate the murders.