Islamist fighters injured a further 19 people and seized two armoured cars in northern Sinai, while three civilians were killed in four other attacks.
Islamist militants have killed at least 15 soldiers in an attack on an army checkpoint in northern Egypt.
Security officials said a further 19 people were injured, while two armoured cars were seized in the Sinai peninsula.
They said four other attacks on army checkpoints at about the same time killed three civilians and wounded another 13. These appear to have been aimed at diverting attention from the main assault on the checkpoint south of the town of Sheikh Zuweid, the officials said.
It is believed the militants may have taken soldiers hostage when they seized the armoured vehicles and drove away. The attackers failed to capture a US-made Abrams tank because its crew drove it to a nearby army checkpoint, the officials added.
Islamist fighters have launched a series of complex attacks and ambushes in recent months, despite a large-scale military campaign to suppress the growing insurgency in northern Sinai, which borders Israel and Gaza. Thursday’s attack mirrored past raids in the same region.
Attacks mainly targeting the Egyptian security forces have spiked since the 2013 military overthrow of the former president Mohamed Morsi, following widespread protests against his divisive rule. A Sinai-based group that pledged allegiance to Islamic State last year has claimed responsibility for most of the attacks.