North Sinai locals have found three corpses with bullet wounds, raising the number of bodies found in similar circumstances to nine since the beginning of the week, Al-Ahram Arabic news website reported.
A number of bodies have been found either shot or decapitated in the restive peninsula over the past few months.
Egypt's most active militant group, Ansar Beit Al-Maqdis, has already claimed responsibility for killing at least 12 people by decapitation, accusing them of collaborating with the Egyptian army or Israeli intelligence.
Meanwhile, a conscript was injured in an armed attack on Sheikh Zuweid police station on Monday.
Egypt's military has been battling a jihadist insurgency in Sinai for almost a decade, which has intensified over the past year and a half. The army is currently creating a buffer zone on the Rafah–Gaza border.
Hundreds of police and soldiers have been killed in attacks, while the military has announced killing and arresting hundreds of alleged terrorists.