An Egyptian soldier was shot dead Monday afternoon on the main airport road in southern el-Arish, bringing Monday’s death toll to six.
Security sources told a Ma’an reporter in el-Arish that the officer was shot while looking out from an armored vehicle patrolling the airport road.
The vehicle came suddenly under fire from behind bushes and olive trees, they said.
The victim as 21-year-old Ahmad Abdul-Karim Muhammad, who received a gunshot to the chest.
Gunmen in the Sinai Peninsula, a hotbed of Islamist militant activity, killed three policemen and a soldier hours earlier while shooting dead a civilian in another attack, officials said.
Masked attackers shot three policemen guarding a police station in the north Sinai town before fleeing, a security official said.
Later, unidentified assailants in a car fired at an armored military vehicle in the south of the town, killing a soldier before fleeing, said the same source.
In the Sheikh Zuwayed area, near the border with the Gaza Strip, gunmen opened fire near a checkpoint, killing a civilian, another official said.
Militants in Sinai intensified their campaign against security forces after the military ousted Islamist president Mohamed Morsi on July 3.
Dozens of soldiers and policemen have been killed in daily attacks, as the army has poured troops and armour into the lawless peninsula that straddles Africa and Asia to crush the insurgency.
The Sinai offensive comes as part of a massive crackdown by the army-installed authorities on Islamists, which has seen hundreds killed and more than 2,000 arrested nationwide.
Morsi, the country's first democratically elected leader, is himself detained, as is the leadership of his Muslim Brotherhood.

Six Egyptian soldiers have been killed in the army's ongoing crackdown on militants in the Sinai peninsula. (AFP/File)